The DOI matches its Crossref record; 72 of the 73 references it cites were found in a registry or an index; 1 of the 38 sources its claims cite were checked for support.
Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D2Dopamine Receptors
Open accessAbstract
A role for dopamine (DA) in the regulation of clock genes in the mammalian brain is suggested by evidence that manipulations of DA receptors can alter the expression of some clock genes outside the suprachiasmatic nucleus (SCN), the master circadian clock. The role of endogenous DA in the regulation of clock gene expression is unknown. Here, we demonstrate a direct relationship between extracellular DA levels and the rhythm of expression of the clock protein PERIOD2 (PER2) in the dorsal striatum of the male Wistar rat. Specifically, we show that the peak of the daily rhythm of extracellular DA in the dorsal striatum precedes the peak of PER2 by ∼6 h and that depletion of striatal DA by 6-hydroxydopamine or α-methyl-para-tyrosine or blockade of D 2 DA receptors by raclopride blunts the rhythm of striatal PER2. Furthermore, timed daily activation of D 2 DA receptors, but not D 1 DA receptors, restores and entrains the PER2 rhythm in the DA-depleted striatum. None of these manipulations had any effect on the PER2 rhythm in the SCN. Our findings are consistent with the idea that the rhythm of expression of PER2 in the dorsal striatum depends on daily dopaminergic activation of D 2 DA receptors. These observations may have implications for circadian abnormalities seen in Parkinson's disease.
Overview
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Written from the paper’s full text.
TL;DR
Endogenous dopamine in the rat dorsal striatum regulates the daily rhythm of PER2, primarily via daily activation of D2 dopamine receptors. Depleting or blocking dopamine blunts striatal PER2, while timed D2/3 agonist treatment restores and entrains the rhythm without affecting the SCN.
Key findings
- Extracellular dopamine in the dorsal striatum peaks in the middle of the dark phase and precedes the dorsal striatum PER2 peak by ~6 h; PER2 peaks at ZT1 in dorsal striatum but at ZT13 in the SCN.
- Unilateral 6-OHDA lesions of the medial forebrain bundle blunt the dorsal striatum PER2 rhythm on the lesioned side, with significant reductions at ZT1 and ZT19, while SCN PER2 is unaffected.
- AMPT treatment reduced dorsal striatum dopamine content by 95% at ZT13 and 88% at ZT1, reduced PER2 at ZT1, and slightly increased PER2 at ZT13; SCN PER2 was unchanged.
- Chronic raclopride (D2 antagonist) reduced dorsal striatum PER2 at ZT1, whereas SCH 23390 (D1 antagonist) had no effect. Daily quinpirole (D2/3 agonist) at ZT1 restored and reversed the PER2 rhythm in 6-OHDA-lesioned striatum, increasing PER2 at ZT13; daily SKF 81297 (D1 agonist) and continuous quinpirole infusion had no effect.
Methods
- Male Wistar rats (n = 172 total) housed on a 12 h light/dark cycle; experiments used unilateral 6-OHDA medial forebrain bundle lesions, AMPT injections, osmotic minipumps for D1/D2 antagonists or agonists, and daily agonist injections.
- PER2 and PER1 immunoreactive nuclei were counted in dorsal striatum and SCN; DAT staining confirmed lesions; RT-PCR measured Per2 transcription; in vivo microdialysis measured extracellular dorsal striatum dopamine; wheel-running activity was monitored.
- Analyses used mixed-model or two-way ANOVA with ZT and treatment/lesion as factors, followed by Bonferroni-corrected post hoc tests or t tests; α = 0.05.
Limitations
- The paper states that the mechanisms whereby dopamine depletion and D2 receptor activation suppress and restore PER2 remain unresolved, and it leaves open a possible role for noradrenaline because AMPT also prevents noradrenaline synthesis.
- Evident from the text: the dopamine rhythm was measured in only three rats, and several experimental groups had small n values (e.g., 2–3 per ZT in some conditions), limiting precision.
- Evident from the text: the phase relationship between dopamine and PER2 is correlational, and the study does not identify the molecular pathway linking D2 receptor activation to Per2 transcription.
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Claims the paper makes
102 Own result · 25 Own interpretation · 17 Not checked yet · 5 Own method · 1 Supported so far · 1 No basis given
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“depletion of striatal DA by 6-hydroxydopamine or ␣-methyl-para-tyrosine or blockade of D 2 DA receptors by raclopride blunts the rhythm of striatal PER2”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Rests on an assumption: Raclopride acts selectively as a D2 dopamine receptor antagonist.
- Rests on an assumption: Unilateral 6-OHDA injection into the MFB selectively destroys dopaminergic inputs to the dorsal striatum without affecting other neurotransmitter systems.
- Rests on an assumption: AMPT selectively inhibits tyrosine hydroxylase and depletes dopamine without affecting other catecholamines.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“the peak of the daily rhythm of extracellular DA in the dorsal striatum precedes the peak of PER2 by ϳ6 h”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Abstract
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“None of these manipulations had any effect on the PER2 rhythm in the SCN.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Abstract
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“we demonstrate a direct relationship between extracellular DA levels and the rhythm of expression of the clock protein PERIOD2 (PER2) in the dorsal striatum of the male Wistar rat.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Abstract
boostedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In the SCN, the rhythm of PER2 expression peaks in the evening, in antiphase to that in the dorsal striatum (Figs. 1, 2b).”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Phase relationship between locomotor activity, PER2 expression, and extracellular DA levels in the dorsal striatum
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“PER2 expression in the 6-OHDA-lesioned striatum was significantly reduced at ZT1 (t (5) ϭ 13.60; p Ͻ 0.01) and ZT19 (t (3) ϭ 7.41; p Ͻ 0.01).”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression after unilateral 6-OHDA lesion
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“a similar reduction in activity levels was observed in vehicle-treated rats”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression after unilateral 6-OHDA lesion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This finding indicates that the blunting of peak PER2 expression in the dorsal striatum after a unilateral 6-OHDA lesion does not recover with time, even when rats have access to running wheels in the intervening period.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression after unilateral 6-OHDA lesion
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“PER2 expression in the SCN was not affected in either treatment group”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression after unilateral 6-OHDA lesion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In the SCN (Fig. 4d), the 6-OHDA injection had no effect on the normal rhythm of PER2-IR in either the lesioned or the intact hemispheres”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression after unilateral 6-OHDA lesion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Probably not a substantial claim. 13
- It may state two separate claims as one. 31
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“Rhythmic clock gene expression is not limited to the SCN, however, and has been characterized in several other regions of the brain and in peripheral tissues (Abe et al., 2002;Shieh, 2003;Amir et al., 2004;Lamont et al., 2005;Guilding and Piggins, 2007).”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Introduction
What the sources say
- Supportedcites Abe et al., 2002 source
The paper reports rhythmic Per1 expression in multiple brain regions outside the SCN (opening section; Discussion). Its introductory section also describes circadian molecular expression in non-neural tissues, citing earlier studies for that peripheral-tissue finding. (LLM, conf=0.90)
- Not checked yetcites Shieh, 2003
- Not checked yetcites Amir et al., 2004
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
- Supported
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“timed daily activation of D 2 DA receptors, but not D 1 DA receptors, restores and entrains the PER2 rhythm in the DA-depleted striatum”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Rests on an assumption: Quinpirole acts selectively as a D2/3 dopamine receptor agonist.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“the rhythm of PER2 expression in the dorsal striatum peaks in the morning, at the beginning of the light phase (ZT1), and reaches its trough in the evening, at the beginning of the dark phase (ZT13).”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Phase relationship between locomotor activity, PER2 expression, and extracellular DA levels in the dorsal striatum
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“the 6-OHDA injection severely blunted the rhythm of PER2 expression in the lesioned hemisphere, but did not affect the normal PER2 rhythm on the intact side”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression after unilateral 6-OHDA lesion
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“wheel-running activity occurs primarily in the dark phase and is absent during the light phase.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Phase relationship between locomotor activity, PER2 expression, and extracellular DA levels in the dorsal striatum
plainn = 3- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In the SCN, the normal rhythm of PER1 expression is similar to the rhythm of PER2 and peaks near ZT13.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER1 expression after unilateral 6-OHDA lesion
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“the normal rhythm of PER1 expression approximates the rhythm of PER2 in this region and peaks near ZT1.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER1 expression after unilateral 6-OHDA lesion
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“daily quinpirole injections restored the daily variation of PER2 expression in the lesioned striatum while suppressing nighttime activity, but had no effect on PER2 expression in the intact hemisphere.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Mechanisms of PER2 modulation by DA in the dorsal striatum
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Neither daily injections nor continuous infusions of a D 1 DA agonist were effective.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Daily, timed stimulation of D 2 receptors regulates PER2 in the dorsal striatum
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“chronic delivery of quinpirole (Fig. 12b) or SKF 81297 (Fig. 12c) at the doses used did not alter the effect of lesions on PER2 expression in the dorsal striatum nor did they alter PER2 expression in the intact hemisphere.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Effect of D 1 or D 2/3 DA receptor agonist injections on PER2 expression and wheel running in 6-OHDA-lesioned rats
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“AMPT depletion of catecholamines strongly reduced PER2 expression in this region, as well as in M1 and DG, which receive NA inputs.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Mechanisms of PER2 modulation by DA in the dorsal striatum
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Daily injections of a D 2 DA receptor agonist, given to induce a peak of activation of DA receptors at a time of day when DA levels are normally low, not only restored, but shifted the daily peak of PER2 in the lesioned striatum.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Daily, timed stimulation of D 2 receptors regulates PER2 in the dorsal striatum
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“When striatal DA was depleted unilaterally using 6-OHDA, the peak expression of PER2 on the lesioned side was strongly suppressed and the daily rhythm of PER2 in this region was blunted both 2 and 4 weeks after surgery.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Daily, timed stimulation of D 2 receptors regulates PER2 in the dorsal striatum
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Unilateral depletion of striatal DA, which strongly blunted the rhythm of PER2 expression on the lesioned side, did not disrupt the daily activity rhythm even though the level of nighttime activity was reduced.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Mechanisms of PER2 modulation by DA in the dorsal striatum
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The daily fluctuations in extracellular striatal DA levels (c) and wheelrunning activity (d) peak at night, preceding the peak of PER2 in the striatum.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In vivo microdialysis sampling in the dorsal striatum shows that extracellular DA levels are lowest during the middle of the light phase and highest in the middle of the dark phase”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The daily fluctuations in extracellular striatal DA levels (c) and wheelrunning activity (d) peak at night, preceding the peak of PER2 in the striatum.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“in the SCN, PER2-IR nuclei are most abundant around ZT13”
- Also stated in: § Functional significance of PER2 regulation by DA · plain
“In the SCN, PER2 expression is greatest at ZT13, near the beginning of the dark phase, and is lowest during the light phase.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Also stated in: § Functional significance of PER2 regulation by DA · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Neither treatment affected daily wheel-running activity”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Wheel-running activity is also greatest during the dark phase and is virtually absent during the light phase”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In the dorsal striatum, PER2-IR nuclei are most abundant around ZT1”
- Also stated in: § Functional significance of PER2 regulation by DA · plain
“In the dorsal striatum, PER2 expression is greatest at ZT1, near the beginning of the light phase, and is lowest during the dark phase”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Also stated in: § Functional significance of PER2 regulation by DA · plain
None of the sources cited for this claim have been checked yet.
In the paper
“Circadian rhythms of physiology and behavior are generated by a core set of clock genes, which regulate their own expression in a 24 h transcriptional-translational feedback cycle (for review, see Reppert and Weaver, 2001;Ko and Takahashi, 2006).”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Introduction
What the sources say
- Not checked yetcites Reppert and Weaver, 2001
- Not checked yetcites Ko and Takahashi, 2006
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“The role of endogenous DA in the regulation of clock gene expression is unknown.”
- Also stated in: § Introduction · hedged
“There is no direct evidence, however, that endogenous DA regulates rhythmic expression of clock genes.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Abstract
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
- Also stated in: § Introduction · hedged
None of the sources cited for this claim have been checked yet.
In the paper
“The specificity of the PER2 and PER1 primary antibodies was previously confirmed with blocking experiments, in which addition of the PER2 peptide or the PER1 peptide (1 g/ml in PBS) to the primary incubation solution prevented staining of PER2 or PER1 expression, respectively, in the tissue (Hastings et al., 1999;Field et al., 2000).”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Osmotic minipump surgery.
What the sources say
- Not checked yetcites Hastings et al., 1999
- Not checked yetcites Field et al., 2000
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Thus, the rhythms of PER2 expression in the SCN, extracellular DA levels in the dorsal striatum, and wheel running are in phase with one another, but are in antiphase to the rhythm of PER2 expression in the dorsal striatum.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Phase relationship between locomotor activity, PER2 expression, and extracellular DA levels in the dorsal striatum
plaincorrelationaln = 3- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“We found no differences between these primary antibodies in the pattern or amount of staining for PER2 in a number of different brain regions.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Osmotic minipump surgery.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
None of the sources cited for this claim have been checked yet.
In the paper
“Although signals from the SCN are required to maintain and coordinate rhythmic gene expression in the brain and periphery, these extra-SCN rhythms can also be influenced independently by a variety of other signals, including steroid hormones, stressors, and restricted feeding schedules (Takahashi et al., 2001;Wakamatsu et al., 2001;Perrin et al., 2006;Segall et al., 2006;Angeles-Castellanos et al.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Introduction
What the sources say
- Not checked yetcites Takahashi et al., 2001
- Not checked yetcites Wakamatsu et al., 2001
- Not checked yetcites Perrin et al., 2006
plainconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Among these genes, Period2 (Per2) plays a critical role in the regulation of this 24 h rhythm by serving as the interface between the negative and positive limbs of the cycle (Chen et al., 2009).”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Introduction
What the sources say
- Not checked yetcites Chen et al., 2009
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Rats were left in their home cages for at least 10 d to entrain to the LD cycle before the start of each experiment and were randomly assigned to an experimental condition.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Subjects.
plainn = 172- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“We found that the rhythms of PER2 expression were consistent across these regions and that the effects of each experimental manipulation on their expression did not vary within the striatum.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Microscopy.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In mammals, the master circadian clock resides in the suprachiasmatic nucleus (SCN), and the phase of rhythmic clock gene expression in this region is entrained by environmental light (Lowrey and Takahashi, 2000).”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Introduction
What the sources say
- Not checked yetcites Lowrey and Takahashi, 2000
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“In the experiments involving unilateral injections of 6-OHDA toxin into the MFB, data were analyzed only from those rats with complete unilateral lesions, as confirmed by an absence of DAT staining in the dorsal striatum ipsilateral to the 6-OHDA injection.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Statistical analyses of IR nuclei counts and Per2 transcription levels.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
None of the sources cited for this claim have been checked yet.
In the paper
“In particular, activation of D 2 receptors has been demonstrated to modulate the circadian effects of light on locomotor activity in mice (Doi et al., 2006) and to regulate expression of clock genes in the retina (Besharse et al., 2004;Yujnovsky et al., 2006) and striatum (Imbesi et al., 2009;Sahar et al., 2010), a region important for motor control, learning, cognition, and reward.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Introduction
What the sources say
- Not checked yetcites Doi et al., 2006
- Not checked yetcites Besharse et al., 2004;Yujnovsky et al., 2006
- Not checked yetcites Imbesi et al., 2009;Sahar et al., 2010
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“The doses of SCH 23390 and raclopride were chosen on the basis of previous studies indicating dose ranges that were effective in occupying ϳ80% of striatal D 1 or D 2 DA receptors and that did not impede motor function”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression during chronic treatment with DA receptor antagonists
What the sources say
- Not checked yetcites Creese and Chen, 1985
- Not checked yetcites Neisewander et al., 1998
- Not checked yetcites Wadenberg et al., 2001; Kapur et al., 2003
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The results of our 6-OHDA experiments indicate that a unilateral lesion of dopaminergic projections and subsequent depletion of DA in the dorsal striatum significantly blunts the normal rhythm of PER2 expression in this region without affecting the rhythm in the SCN.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression after inhibition of tyrosine hydroxylase
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Drug doses were in the range shown previously to enhance expression of immediate-early genes, striatal peptides, and electrophysiological responses of striatal neurons in 6OHDA-lesioned rats”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Effect of D 1 or D 2/3 DA receptor agonist injections on PER2 expression and wheel running in 6-OHDA-lesioned rats
What the sources say
- Not checked yetcites Gerfen et al., 1990, 1995
- Not checked yetcites Hu et al., 1992
- Not checked yetcites Zhang et al., 2007; Ballion et al., 2009
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
In the paper
“changes in the expression of peptides and receptors in striatal medium spiny neurons that develop after a unilateral 6-OHDA lesion can be reversed with intermittent or chronic DA receptor agonist treatment”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Effect of D 1 or D 2/3 DA receptor agonist injections on PER2 expression and wheel running in 6-OHDA-lesioned rats
What the sources say
- Not checked yetcites Gerfen et al., 1990
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These results suggest that the normal PER2 rhythm in the dorsal striatum depends on the availability of D 2 , but not D 1 DA receptors.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression during chronic treatment with DA receptor antagonists
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“extracellular DA levels peak in the middle of the dark (active) phase and fall during the light (inactive) phase of the daily cycle”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Daily, timed stimulation of D 2 receptors regulates PER2 in the dorsal striatum
What the sources say
- Not checked yetcites Paulson and Robinson, 1994
- Not checked yetcites Castan ˜eda et al., 2004
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“PER2 expression peaks at the beginning of the light phase and reaches its trough near the beginning of the dark phase”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Daily, timed stimulation of D 2 receptors regulates PER2 in the dorsal striatum
What the sources say
- Not checked yetcites Amir et al., 2006
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“daily stimulation of D 2 , but not D 1 DA receptors, restores and entrains the PER2 rhythm in the DA-depleted striatum.”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Daily, timed stimulation of D 2 receptors regulates PER2 in the dorsal striatum
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“After a 6-OHDA lesion, however, the expression of D 2 DA receptors on cell bodies is lost through destruction of DA fibers, whereas postsynaptic expression of D 2 DA receptors in medium spiny neurons is upregulated”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Mechanisms of PER2 modulation by DA in the dorsal striatum
What the sources say
- Not checked yetcites Gerfen et al., 1990
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The paper relies on this without support.
Raclopride acts selectively as a D2 dopamine receptor antagonist.
“blockade of D 2 DA receptors by raclopride”
The paper relies on this without support.
Quinpirole acts selectively as a D2/3 dopamine receptor agonist.
“D 1 and D 2/3 DA receptor agonists, delivered either by timed daily injection”
The paper relies on this without support.
Unilateral 6-OHDA injection into the MFB selectively destroys dopaminergic inputs to the dorsal striatum without affecting other neurotransmitter systems.
“One hour before surgery, rats were injected intraperitoneally with desipramine (2.5 mg/kg) to protect noradrenergic fibers from the 6-OHDA toxin.”
The paper relies on this without support.
AMPT selectively inhibits tyrosine hydroxylase and depletes dopamine without affecting other catecholamines.
“injections of the tyrosine hydroxylase inhibitor ␣-methyl-para-tyrosine (AMPT)”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“We have recently reported that striatal dopamine levels exhibit daily rhythms with nocturnal peaks in mice (Agostino et al., 2011a), as had been previously demonstrated in rats (Castaneda et al., 2004, Hood et al., 2010).”
From Circadian dysregulation in Parkinson's disease (2017) · cites this paper as Hood et al., 2010
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER1 expression after unilateral 6-OHDA lesion
“main effect of ZT, F (3,12) ϭ 10.53, p Ͻ 0.01; main effect of lesion, F (1,12) ϭ 21.60, n.s.; ZT by lesion, F (3,12) ϭ 11.24, p Ͻ 0.05”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
“SCN (b) in rats killed at ZT1, 7, 13, and 19, 2 weeks after 6-OHDA treatment (n ϭ 5-6 per ZT).”
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > PER2 expression after inhibition of tyrosine hydroxylase
“independent-samples t test, t (5) ϭ Ϫ3.22, p Ͻ 0.05”
§ Endogenous Dopamine Regulates the Rhythm of Expression of the Clock Protein PER2 in the Rat Dorsal Striatum via Daily Activation of D 2 Dopamine Receptors > Functional significance of PER2 regulation by DA
“b, In the dorsal striatum, AMPT treatment decreased daytime PER2 expression at ZT1 and increased PER2 at ZT13 compared with saline controls (expressed as mean PER2-IR nuclei Ϯ SEM at each ZT; n ϭ 4 per treatment group per ZT; *p Ͻ 0.05).”
Citations
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Metadata
- Authors
- Hood, S., Cassidy, P., Cossette, M.-P., Weigl, Y., Verwey, M., Robinson, B., Stewart, J., & Amir, S.
- Affiliations
- Concordia University (CA)
- Corresponding author
- Amir, Shimon
- Venue
- The Journal of Neuroscience
- Publisher
- Society for Neuroscience
- Published
- 2010-10-20
- Volume
- 30
- Issue
- 42
- Pages
- 14046-14058
- ISSN
- 0270-6474 (ISSN-L)
- 1529-2401
- PMC
- PMC6634752
- OpenAlex
- W1994354389
- Semantic Scholar
- 1e97e34ebe3618b16bc6ac1f8b26c1ab8625ec3b
- Cited by
- 246
- References
- 73
- Citations by year
- 2026: 11 · 2025: 11 · 2024: 13 · 2023: 17 · 2022: 17 · 2021: 20 · 2020: 17 · 2019: 13 · 2018: 28 · 2017: 20 · 2016: 14 · 2015: 14 · 2014: 12 · 2013: 13 · 2012: 12
- FWCI
- 5.63
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Journal of Neuroscience (publishedVersion, cc-by-nc-sa)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Concordia University
- Canadian Institutes of Health Research
- Topics
- Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
- Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurotransmitter Receptor Influence on Behavior
- Health Sciences › Medicine › Clinical Neurology › Parkinson's Disease Mechanisms and Treatments
- Keywords
- dopamine, dopamine D2 receptor, Per2, clock genes, circadian rhythm, dorsal striatum, extracellular dopamine, 6-hydroxydopamine, alpha-methyl-p-tyrosine, raclopride, suprachiasmatic nucleus, Parkinson's disease, circadian entrainment
- MeSH terms
- Animals, Cell Count, Chromatography, High Pressure Liquid, Corpus Striatum, Dopamine, Gene Expression Regulation, Immunohistochemistry, Male, Medial Forebrain Bundle, Motor Activity, RNA, Suprachiasmatic Nucleus, Sympathectomy, Chemical, Sympatholytics, Tyrosine 3-Monooxygenase, Oxidopamine, Rats, Wistar, Receptors, Dopamine D2, Microdialysis, Reverse Transcriptase Polymerase Chain Reaction, Rats, Period Circadian Proteins, Dopamine D2 Receptor Antagonists
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
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