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Cited by 32Nicotinic Acetylcholine Receptors StudySmoking Behavior and CessationNeurotransmitter Receptor Influence on Behavior

123I-5-IA-85380 SPECT Imaging of Nicotinic Acetylcholine Receptor Availability in Nonsmokers: Effects of Sex and Menstrual Phase

Open access
Cosgrove, K. P., Mitsis, E. M., Bois, F., Frohlich, E., Tamagnan, G. D., Krantzler, E., Perry, E., Maciejewski, P. K. +7 more·2007·Journal of Nuclear Medicine
DOI 10.2967/jnumed.107.042317
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Abstract

UNLABELLED: The study of the effects of sex and hormones on brain chemistry and neurotransmission is of increasing importance as evidence emerges of sex differences in behavioral symptoms and treatment response in neuropsychiatric disorders. The nicotinic acetylcholine receptor (nAChR) system has been implicated in a variety of psychiatric disorders, including tobacco smoking, for which there is strong evidence supporting sex differences in behaviors and response to smoking cessation treatments. We examined the availability of nAChR containing the beta(2) subunit in healthy men and women and the influence of menstrual phase among women. METHODS: Ten men and 19 women nonsmokers underwent one (123)I-5-IA-85380 ((123)I-5-IA) SPECT scan and one MRI scan. A subset of 9 women, aged 18-39 y, underwent a second (123)I-5-IA scan. These 9 women were scanned during the early follicular (days 4-7 in 8 subjects and day 11 in 1 subject) and mid-luteal (days 19-25) phases of their menstrual cycle. Hormone levels were measured in all women to confirm the phase of the cycle. RESULTS: Regional brain activity (kBq/cm(3)) was higher (39%-54%) in women than in men nonsmokers. When regional brain activity was normalized to total plasma parent to correct for individual differences in radiotracer metabolism (V(T)'), differences of 10%-16% were observed, with women greater than men. In contrast, when regional brain activity was normalized to free plasma parent (V(T)), there was less than a 4% difference by sex in regional brain beta(2)-nAChR availability. These sex differences in kBq/cm(3) and V(T)' resulted from significantly higher levels of total plasma parent, free fraction (f(1)), and free plasma parent in women than in men nonsmokers. No differences in plasma measures or brain beta(2)-nAChR availability were observed across the menstrual cycle for any outcome measure. CONCLUSION: Overall, these findings demonstrate no significant difference in brain beta(2)-nAChR availability between men and women nonsmokers or across the menstrual cycle. Importantly, these findings demonstrate sex differences in radiotracer metabolism and plasma protein binding and highlight the critical need to measure plasma radiotracer levels and f(1) in studies that include both sexes.

AI snapshot

Written from the paper’s full text.

TL;DR

In healthy nonsmokers, brain β2-nicotinic acetylcholine receptor availability did not differ significantly between men and women or across the menstrual cycle. However, women showed higher uncorrected brain radiotracer activity and higher total plasma parent, free fraction, and free plasma parent, highlighting sex differences in radiotracer metabolism and protein binding.

Key findings

  • No significant sex difference in β2-nAChR availability when using V_T, which corrects for both radiotracer metabolism and plasma protein binding; V_T differences were less than 4% by sex.
  • Uncorrected regional brain activity (kBq/cm³) was 39%–54% higher in women than men, and V_T′ differences were 10%–16%, but these appeared driven by plasma factors rather than receptor availability.
  • Women had significantly greater free fraction (f₁; t₂₇ = 2.50, P = 0.02), total plasma parent (t₂₇ = 2.03, P = 0.05), and free plasma parent (t₂₇ = 2.05, P = 0.05) than men.
  • No significant differences in plasma measures or brain β2-nAChR availability were observed between early follicular and mid-luteal phases in the 9 women scanned twice.

Methods

  • Ten men and 19 women nonsmokers underwent one ¹²³I-5-IA-85380 SPECT scan and one MRI scan; a subset of 9 women underwent a second SPECT scan in early follicular and mid-luteal phases.
  • Regional brain activity, V_T′, and V_T were measured in β2-nAChR-containing regions including frontal, parietal, anterior cingulate, temporal, and occipital cortices, thalamus, striatum, and cerebellum.
  • For study 1, principal-component analysis reduced correlated regional measures, followed by unpaired t tests; for study 2, paired t tests compared menstrual phases.

Limitations

  • Stated: the study could not determine the effect of race on β2-nAChR availability; it examined nonsmokers under age 45, so effects across the lifespan are unknown; and no sex difference in nonsmokers does not preclude a difference in smokers.
  • Stated: ¹²³I-5-IA SPECT may be confounded by endogenous acetylcholine occupancy, it is unclear whether cell-surface or internalized receptors are measured, and other nAChR subtypes may underlie behavioral sex differences.
  • Evident from the text: there is no appropriate reference region for this radiotracer, so nondisplaceable uptake could not be measured; study 2 was not counterbalanced for scan order, and 4 women had luteal progesterone levels suggesting anovulatory cycles, though results did not differ when they were excluded.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.2967/jnumed.107.042317

Cites

49 of 49 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 23 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Regional brain activity (kBq/cm3) was 39%-54% higher in women than in men nonsmokers.

    “Regional brain activity (kBq/cm 3 ) was higher (39%-54%) in women than in men nonsmokers.”
    • Also stated in: § DISCUSSION · boosted
      “the profound sex difference in uncorrected (kBq/cm 3 ) measures of regional brain uptake (39%-54%)”
    Quote in the paperSubstantial claim
  • Findingown data

    When regional brain activity was normalized to total plasma parent (VT9), women showed 10%-16% greater values than men.

    “When regional brain activity was normalized to total plasma parent to correct for individual differences in radiotracer metabolism (V T 9), differences of 10%-16% were observed, with women greater than men.”
    • Also stated in: § DISCUSSION · plain
      “as compared with the outcome measure that corrected for metabolism only (but not protein binding), V T 9 (10%-16%).”
    Quote in the paperSubstantial claim
  • Findingown data

    When regional brain activity was normalized to free plasma parent (VT), there was less than a 4% difference by sex in regional brain b2-nAChR availability.

    “In contrast, when regional brain activity was normalized to free plasma parent (V T ), there was less than a 4% difference by sex in regional brain b 2 -nAChR availability.”
    • Also stated in: § Study 1: The Effect of Sex · plain
      “The main V T component did not differ significantly between women and men.”
    • Also stated in: § DISCUSSION · plain
      “there was no difference in b 2 -nAChR availability as evaluated by the outcome measure (V T ) that corrected for both radiotracer metabolism and the f 1 of radiotracer.”
    Quote in the paperSubstantial claim
  • Findingown data

    There were no differences in plasma measures or brain b2-nAChR availability across the menstrual cycle for any outcome measure.

    “No differences in plasma measures or brain b 2 -nAChR availability were observed across the menstrual cycle for any outcome measure.”
    • Also stated in: § DISCUSSION · plain
      “Radiotracer metabolism, plasma protein binding, and brain b 2 -nAChR availability did not differ between the early follicular and mid-luteal phases of the menstrual cycle in women nonsmokers.”
    Quote in the paperSubstantial claim
  • Findingown data

    No significant differences in VT were observed in women between the early follicular and mid-luteal phases in any region of interest.

    “Similarly, no significant differences in V T were observed”
    Quote in the paperSubstantial claim
  • May combine two claims. 13
  • Classified as probably not a substantial claim. 19

  • May combine two claims.

    Findingown data

    Women nonsmokers had significantly higher total plasma parent, free fraction (f1), and free plasma parent than men nonsmokers.

    “These sex differences in kBq/cm 3 and V T 9 resulted from significantly higher levels of total plasma parent, free fraction (f 1 ), and free plasma parent in women than in men nonsmokers.”
    • Also stated in: § Study 1: The Effect of Sex · plain
      “Statistical analyses (t test) also determined that women have significantly greater f 1 (t 27 5 2.50, P 5 0.02), total parent (t 27 5 2.03, P 5 0.05), and plasma free parent (t 27 5 2.05, P 5 0.05) than do men (Fig. 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Radiotracer metabolism and plasma protein binding did not change between the early follicular and mid-luteal phases of the menstrual cycle.

    “Radiotracer metabolism and plasma protein binding-for example, total parent and f 1 -did not change between the early follicular and mid-luteal phases of the menstrual cycle (Fig. 4).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Single principal components explained 96% of variance in kBq/cm3, 88% in VT9, and 91% in VT across brain regions.

    “single components explained 96% of the variance in kBq/cm 3 , 88% of the variance in V T 9, and 91% of the variance in V T across brain regions.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In this study, significant sex differences were found, with higher f1 and total and free parent in women than in men.

    “Specifically, in this study, significant sex differences were found, with higher f 1 and total and free parent in women than in men.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Women have significantly greater f1, total parent, and plasma free parent than men.

    “women have significantly greater f 1 (t 27 5 2.50, P 5 0.02), total parent (t 27 5 2.03, P 5 0.05), and plasma free parent (t 27 5 2.05, P 5 0.05) than do men”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The sex difference in VT9 is due to higher 123I-5-IA uptake in women than in men, not to greater b2-nAChR availability.

    “thus, because V T 9 does not correct for protein binding, the sex difference is due to a higher 123 I-5-IA uptake in women than in men but not to a greater b 2 -nAChR availability.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    123I-5-IA SPECT has demonstrated significantly higher b2-nAChR availability in recently abstinent tobacco smokers than in age-and sex-matched nonsmokers.

    “123 I-5-IA SPECT has demonstrated significantly higher b 2 -nAChR availability in recently abstinent tobacco smokers than in age-and sex-matched nonsmokers (23).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [23]

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    Estradiol potentiates acetylcholine-evoked currents in human neuronal nAChRs by interacting at the a4 subunit.

    “estradiol has been shown to potentiate acetylcholine-evoked currents in human neuronal nAChRs by interacting at the a 4 subunit (18).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [18]

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    Radiotracer metabolism and plasma protein binding differ between men and women.

    “these findings demonstrate sex differences in radiotracer metabolism and plasma protein binding”
    • Also stated in: § DISCUSSION · hedged
      “suggesting that the radiotracer 123 I-5-IA is metabolized differently between men and women and that the amount of 123 I-5-IA bound to plasma proteins differs between men and women.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    High test-retest reliability and validity were recently reported for 123I-5-IA SPECT.

    “High test-retest reliability and validity were recently reported for 123 I-5-IA SPECT (22),”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [22]

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    VT9 had been shown to be a more reliable and less variable outcome measure than VT.

    “V T 9 had been shown to be a more reliable and less variable outcome measure than V T (34).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [34]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    The second SPECT scan for study 2 subjects was coregistered to the same position as the first scan to apply the same ROI template.

    “the second SPECT scan for the subjects in study 2 was coregistered to the same position as the first scan in order to apply the same region-of-interest template for each subject.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    The sex difference in f1 and total parent became significant when sample size increased to 29 and was a contributing factor to the observed sex difference in brain b2-nAChR availability.

    “when the sample size increased to 29 (19 women and 10 men), the sex difference in f 1 and total parent became significant and a contributing factor to the observed sex difference in brain b 2 -nAChR availability.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    All women of childbearing age were required to have a negative pregnancy test during screening and before radiotracer injection on each study day.

    “All women of childbearing age were required to have a negative pregnancy test during the screening process and before radiotracer injection on each study day.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The subjects were not counterbalanced for the order of follicular versus mid-luteal scans.

    “The subjects were not counterbalanced for the order of follicular versus mid-luteal scans.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    In the menstrual cycle study, use of hormonal contraceptives within the previous 6 months was exclusionary.

    “In the menstrual cycle study, use of hormonal contraceptives within the previous 6 mo was exclusionary.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    A 57Co-distributed source was measured with each experiment to control for day-to-day variation in camera sensitivity.

    “A 57 Co-distributed source was measured with each experiment to control for day-to-day variation in camera sensitivity.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductown data

    All subjects received a medical examination to exclude major medical issues or neurologic disorders.

    “All subjects received a medical examination by a study physician to exclude any major medical issues or neurologic disorders.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    The study was approved by the Yale University School of Medicine Human Investigation Committee, the West Haven Veterans Administration Human Subjects Subcommittee, the Radiation Safety Committee, and the Food and Drug Administration.

    “This study was approved by the Yale University School of Medicine Human Investigation Committee, the West Haven Veterans Administration Human Subjects Subcommittee, the Radiation Safety Committee, and the Food and Drug Administration.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Nonsmoking status was confirmed by plasma cotinine <15 ng/mL, urine cotinine <100 ng/mL, and carbon monoxide <11 ppm on the day of intake and the day of the scan.

    “Nonsmoking status was confirmed by plasma cotinine levels of less than 15 ng/mL, urine cotinine levels of less than 100 ng/mL and carbon monoxide levels of less than 11 ppm on the day of intake and the day of the scan.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Hormone levels were measured in all women to confirm the phase of the cycle.

    “Hormone levels were measured in all women to confirm the phase of the cycle.”
    • Also stated in: § Subjects · plain
      “Hormones were analyzed to confirm the phase of the cycle and the premenopausal status.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Anovulatory cycles occur in as many as 38% of cycles in young women.

    “as occurs in as many as 38% of cycles in young women (27)”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [27]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    Two raters conducted the analysis, with variability between raters less than 12% across regions of interest.

    “Two raters conducted the analysis.Variability between the raters was less than 12% across regions of interest.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Another limitation of this study was that we examined men and women nonsmokers under the age of 45 y.

    “Another limitation of this study was that we examined men and women nonsmokers under the age of 45 y.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Study design and conductcitation

    There is no appropriate reference region for 123I-5-IA, so nondisplaceable 123I-5-IA uptake could not be measured.

    “As described previously (25), there is no appropriate reference region for this radiotracer, so nondisplaceable 123 I-5-IA uptake could not be measured.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [25]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    Bonferroni correction for multiple comparisons across 8 brain regions indicated that P values less than 0.00625 were highly significant.

    “Bonferroni correction for multiple comparisons across 8 brain regions indicated that P values of less than 0.00625 were highly significant.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    The small size and blood volume of mice and rats precludes appropriate plasma analysis.

    “Unfortunately, the small size and blood volume of mice and rats precludes appropriate plasma analysis.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Subjects were interviewed using the Structured Clinical Interview of the Diagnostic and Statistical Manual of Mental Disorders to rule out any Axis I disorder.

    “The subjects were interviewed using the Structured Clinical Interview of the Diagnostic and Statistical Manual of Mental Disorders to rule out any Axis I disorder.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    It is likely that radioligand metabolism or protein binding were different between male and female animals.

    “Additionally, it is likely that radioligand metabolism or protein binding were different between male and female animals.”
    Quote in the paperNot a substantial claim
29 of 29

  • The authors state this as an assumption.

    There is no change in affinity of the radiotracer for b2-nAChRs.

    “given the assumptions that there is no change in affinity”

  • The authors state this as an assumption.

    Nondisplaceable (nonspecific and free) uptake does not differ between subjects or between comparison groups.

    “and that nondisplaceable (nonspecific and free) uptake does not differ between subjects or between comparison groups.”

  • The paper relies on this without support.

    It is not known whether nicotinic receptor availability differs between living men and women.

    “It is not known whether nicotinic receptor availability differs between living men and women.”

  • The paper relies on this without support.

    The mechanisms underlying sex differences in smoking behaviors are unclear.

    “however, the mechanisms underlying these differences are unclear.”

  • The paper relies on this without support.

    Few in vivo PET or SPECT neuroreceptor imaging studies have examined sex differences or changes in neurotransmitter levels or receptors across the menstrual cycle in living humans, and there are virtually no data on the effects of menstrual phase on human brain derived from postmortem studies.

    “Few in vivo PET or SPECT neuroreceptor imaging studies have examined sex differences or changes in neurotransmitter levels or receptors across the menstrual cycle in living humans, and there are virtually no data on the effects of menstrual phase on human brain derived from postmortem studies.”

  • The paper relies on this without support.

    Studies examining the effect of sex and menstrual phase on the brain are important because many psychiatric disorders are marked by sex differences in signs and symptoms that may be a consequence of sex differences in brain chemistry.

    “Studies examining the effect of sex and menstrual phase on the brain are important because many psychiatric disorders are marked by sex differences in signs and symptoms that may be a consequence of sex differences in brain chemistry.”

  • The paper relies on this without support.

    A limitation of many neuroreceptor imaging studies is that f1 often is not measured or reported.

    “A limitation of many neuroreceptor imaging studies is that f 1 often is not measured or reported.”
7 of 7

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?

  • The continued significant decrease in β2*-nAChR availability in fully recovered, euthymic, medication-free rMDD subjects suggests that the changes in MDD are not an epiphenomenon of treatment or illness but may be associated with trait vulnerability to depression.

    “The continued, significant decrease in β2*-nAChR availability in fully recovered, euthymic, medication free rMDD subjects suggests that the changes in MDD are not an epiphenomenon of treatment or illness but may be associated with trait vulnerability to depression as demonstrated by us previously for other targets (26, 41, 42).”

    From Persistent β <sub>2</sub> *-Nicotinic Acetylcholinergic Receptor Dysfunction in Major Depressive Disorder (2012) · cites this paper as [41]

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.

  • Study 2 age range falls outside the Study 1 cohort

    Minor

    All nine Study 2 women participated in Study 1, whose women's age range starts at 20 years. The Study 2 range nevertheless starts at 18 years.

  • Reported total dose for men exceeds the stated 8-hour dose

    Minor

    The stated mean bolus plus eight hours of infusion is 323.4 MBq, not 345.1 MBq.

    Reported 345.1 · recomputed 323.4

2 of 2

Cites

Flagged first, then by citations

Research works printed but not linked: 5

  1. Perkins K. Sex differences in nicotine vs. non-nicotine reinforcement as determinants of tobacco smoking. Exp Clin Psychopharmacol. 1996;4:166-177.
  2. Mochizuki T, Villemagne V, Scheffel U, et al. Nicotine induced up-regulation of nicotinic receptors in CD-1 mice demonstrated with an in vivo radiotracer: gender differences. Synapse. 1998;30:116-118.
  3. Staley JK, van Dyck C, Weinzimmer D, et al. 123 I-5-IA-85380 SPECT measurement of nicotinic acetylcholine receptors in human brain by the con- stant infusion paradigm: feasibility and reproducibility. J Nucl Med. 2005;46: 1466-1472.
  4. Mochizuki T, Villemagne VL, Scheffel U, et al. Nicotine induced up-regulation of nicotinic receptors in CD-1 mice demonstrated with an in vivo radiotracer: gender differences. Synapse. 1998;30:116-118.
  5. Staley J, van Dyck CH, Weinzimmer D, et al. Iodine-123 -5-IA-85380 SPECT measurement of nicotinic acetylcholine receptors in human brain by the con- stant infusion paradigm: feasibility and reproducibility. J Nucl Med. 2005;46: 1466-1472.

Cited by

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Related

Authors
Cosgrove, K. P., Mitsis, E. M., Bois, F., Frohlich, E., Tamagnan, G. D., Krantzler, E., Perry, E., Maciejewski, P. K., Epperson, C. N., Allen, S., O'Malley, S., Mazure, C. M., Seibyl, J. P., van Dyck, C. H., & Staley, J. K.
Affiliations
  • Yale University (US)
  • United States Department of Veterans Affairs (US)
  • University of Minnesota (US)
  • Institute for Neurodegenerative Disorders (US)
ORCID
Venue
Journal of Nuclear Medicine
Publisher
Society of Nuclear Medicine
Published
2007-10-01
Volume
48
Issue
10
Pages
1633-1640
ISSN
0161-5505 (ISSN-L)
DOI
10.2967/jnumed.107.042317
OpenAlex
W2078012392
Semantic Scholar
b4c1c5e9bc9ec94d59fa976874c3e2ed5b679ffe
Cited by
31
References
49
Citations by year
2025: 1 · 2024: 1 · 2020: 2 · 2016: 3 · 2015: 3 · 2014: 3 · 2013: 2 · 2012: 4
FWCI
1.32
Type
journal article
Language
en
Open access
Locations
  • Journal of Nuclear Medicine (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • Yale University
  • National Institutes of Health
  • National Institute on Alcohol Abuse and Alcoholism (P50AA015632, P50-AA15632)
  • National Institute of Mental Health (K02MH073090)
  • National Institute on Drug Abuse (KO1DA020651, K02DA021863, R01DA015577, KO2DA021863, K01DA020651, R01DA018359)
  • National Institute of Neurological Disorders and Stroke (NS-044316, K25NS044316)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Nicotinic Acetylcholine Receptors Study
  • Health Sciences › Medicine › Physiology › Smoking Behavior and Cessation
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurotransmitter Receptor Influence on Behavior
Keywords
nicotinic acetylcholine receptors, beta2 subunit, sex differences, menstrual cycle, non-smokers, SPECT imaging, plasma protein binding, radiotracer metabolism
MeSH terms
Adult, Azetidines, Brain, Female, Humans, Male, Menstrual Cycle, Pyridines, Receptors, Nicotinic, Sex Factors, Smoking, Tissue Distribution, Tomography, Emission-Computed, Single-Photon, Radiopharmaceuticals

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