CoChat
Sign Up
Cited by 270Pancreatic function and diabetesCellular transport and secretionIon channel regulation and function

Exocytosis elicited by action potentials and voltage‐clamp calcium currents in individual mouse pancreatic B‐cells.

Open access
Ammälä, C, Eliasson, L, Bokvist, K, Larsson, O, Ashcroft, F M, Rorsman, P·1993·The Journal of Physiology
DOI 10.1113/jphysiol.1993.sp019966PMC PMC1160506
Open this paper in CoChat — free account

Abstract

1. Measurements of membrane capacitance, as an indicator of exocytosis, and intracellular Ca2+ concentration ([Ca2+]i) were used to determine the Ca2+ dependence of secretion in single pancreatic B-cells. 2. Exocytosis was dependent on a rise in [Ca2+]i and could be evoked by activation of voltage-dependent Ca2+ currents. The threshold for depolarization-induced release was 0.5 microM [Ca2+]i. Once the [Ca2+]i threshold was exceeded, exocytosis was rapidly ( or = four action potentials. 5. Comparison of the rates of exocytosis measured in response to depolarization, mobilization of Ca2+ from intracellular stores or infusion of Ca2+ through the patch pipette suggests that [Ca2+]i at the secretory sites attains a concentration of several micromolar. This is much higher than the average [Ca2+]i detected by microfluorimetry suggesting the existence of steep spatial gradients of [Ca2+]i within the B-cell. 6. Inclusion of inhibitors of Ca2+/calmodulin-dependent protein kinase II in the intracellular solution reduced the depolarization-induced exocytotic responses suggesting this enzyme may be involved in the coupling between elevation of [Ca2+]i to stimulation of the secretory machinery. 7. The size of the unitary exocytotic event was 2 fF, corresponding to a secretory granule diameter of 250 nm. 8. Over short periods, exocytosis may be extremely fast (1 pF/s or 500 granules/s), which is much higher than the rate of endocytosis (18 fF/s or 9 granules/s). Since the latter is in bett…

Integrity signals

Registry

Crossref · 10.1113/jphysiol.1993.sp019966

Cites

Statistics

Recomputing p-values needs the paper’s full text.

Claims the paper makes

We couldn’t retrieve this paper’s full text, so its claims and self-check weren’t run. The registry and citation checks still apply.

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?

  • Exocytosis is triggered by depolarizations above -30 mV, is maximal around zero mV and then undergoes a secondary decrease at more positive voltages.

    “Exocytosis is triggered by depolarizations above -30 mV, is maximal around zero mV and then undergoes a secondary decrease at more positive voltages (Figure 19B).”

    From Pancreatic β-Cell Electrical Activity and Insulin Secretion: Of Mice and Men (2018) · cites this paper as [14]

  • The ∩-shaped voltage dependence of exocytosis mirrors that of depolarization-evoked Ca2+ entry and the associated elevation of [Ca2+]i.

    “This ∩-shaped voltage dependence mirrors that of depolarization-evoked Ca2+ entry (see Figure 9) and the associated elevation of [Ca2+]i (14).”

    From Pancreatic β-Cell Electrical Activity and Insulin Secretion: Of Mice and Men (2018) · cites this paper as [14]

Cited by

Sorted by citations

Authors
Ammälä, C., Eliasson, L., Bokvist, K., Larsson, O., Ashcroft, F. M., & Rorsman, P.
Affiliations
University of Gothenburg (SE)
ORCID
Venue
The Journal of Physiology
Publisher
Wiley
Published
1993-12
Volume
472
Issue
1
Pages
665-688
ISSN
  • 0022-3751 (ISSN-L)
  • 1469-7793
DOI
10.1113/jphysiol.1993.sp019966
PMC
PMC1160506
OpenAlex
W2065011201
Cited by
270
References
0
Citations by year
2026: 2 · 2025: 1 · 2024: 1 · 2023: 3 · 2022: 5 · 2021: 4 · 2019: 3 · 2018: 1 · 2017: 8 · 2016: 7 · 2015: 6 · 2014: 11 · 2013: 3 · 2012: 6
FWCI
18.93
Type
journal article
Language
en
Open access
Licence
onlinelibrary.wiley.com/termsAndConditions#vor (vor)
Locations
  • The Journal of Physiology (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
Wellcome Trust
Topics
  • Health Sciences › Medicine › Surgery › Pancreatic function and diabetes
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Cellular transport and secretion
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Ion channel regulation and function
Keywords
exocytosis, pancreatic beta cells, insulin secretion, action potential, voltage-dependent calcium current, intracellular calcium concentration, calcium-dependent secretion, intracellular calcium stores, calcium/calmodulin-dependent protein kinase II, secretory granules, membrane capacitance, endocytosis, single-cell electrophysiology, mouse islets, repetitive stimulation
MeSH terms
Insulin Secretion, Action Potentials, Animals, Calcium, Electric Stimulation, Endocytosis, Exocytosis, Insulin, Intracellular Fluid, Islets of Langerhans, Isoquinolines, Piperazines, Calcium Channels, Calcium-Calmodulin-Dependent Protein Kinases, 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine, Mice, Calcium-Calmodulin-Dependent Protein Kinase Type 2, In Vitro Techniques

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.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review