Glucagon-like peptide I and glucose-dependent insulinotropic polypeptide stimulate Ca2+-induced secretion in rat alpha-cells by a protein kinase A-mediated mechanism
(1997) In Diabetes 46(5). p.792-800- Abstract
- High-resolution capacitance measurements were used to explore the effects of the gut hormones GLP-I(7-36) amide [glucagon-like peptide I(7-36) amide] and GIP (glucose-dependent insulinotropic polypeptide) on Ca2+-dependent exocytosis in glucagon-secreting rat pancreatic alpha-cells. Both peptides produced a greater than threefold potentiation of secretion evoked by voltage-clamp depolarizations, an effect that was associated with an approximately 35% increase of the Ca2+ current. The stimulatory actions of GLP-I(7-36) amide and GIP were mimicked by forskolin and antagonized by the protein kinase A (PKA)-inhibitor Rp-8-Br-cAMPS. The islet hormone somatostatin inhibited the stimulatory action of GLP-I(7-36) amide and GIP via a cyclic... (More)
- High-resolution capacitance measurements were used to explore the effects of the gut hormones GLP-I(7-36) amide [glucagon-like peptide I(7-36) amide] and GIP (glucose-dependent insulinotropic polypeptide) on Ca2+-dependent exocytosis in glucagon-secreting rat pancreatic alpha-cells. Both peptides produced a greater than threefold potentiation of secretion evoked by voltage-clamp depolarizations, an effect that was associated with an approximately 35% increase of the Ca2+ current. The stimulatory actions of GLP-I(7-36) amide and GIP were mimicked by forskolin and antagonized by the protein kinase A (PKA)-inhibitor Rp-8-Br-cAMPS. The islet hormone somatostatin inhibited the stimulatory action of GLP-I(7-36) amide and GIP via a cyclic AMP-independent mechanism, whereas insulin had no effect on exocytosis. These data suggest that the alpha-cells are equipped with receptors for GLP-I and GIP and that these peptides, in addition to their well-established insulinotropic capacity, also stimulate glucagon secretion. We propose that the reported inhibitory action of GLP-I on glucagon secretion is accounted for by a paracrine mechanism (e.g., mediated by stimulated release of somatostatin that in turn suppresses exocytosis in the alpha-cell). (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1111209
- author
- Ding, W G ; Renström, Erik LU ; Rorsman, Patrik LU ; Buschard, K and Gromada, J
- publishing date
- 1997
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Diabetes
- volume
- 46
- issue
- 5
- pages
- 792 - 800
- publisher
- American Diabetes Association Inc.
- external identifiers
-
- pmid:9133546
- scopus:0030943464
- ISSN
- 1939-327X
- language
- English
- LU publication?
- no
- id
- 1ab52f88-4d01-45dd-a399-2e230c289278 (old id 1111209)
- alternative location
- http://diabetes.diabetesjournals.org/cgi/content/abstract/46/5/792
- date added to LUP
- 2016-04-01 15:39:58
- date last changed
- 2022-04-14 23:18:29
@article{1ab52f88-4d01-45dd-a399-2e230c289278, abstract = {{High-resolution capacitance measurements were used to explore the effects of the gut hormones GLP-I(7-36) amide [glucagon-like peptide I(7-36) amide] and GIP (glucose-dependent insulinotropic polypeptide) on Ca2+-dependent exocytosis in glucagon-secreting rat pancreatic alpha-cells. Both peptides produced a greater than threefold potentiation of secretion evoked by voltage-clamp depolarizations, an effect that was associated with an approximately 35% increase of the Ca2+ current. The stimulatory actions of GLP-I(7-36) amide and GIP were mimicked by forskolin and antagonized by the protein kinase A (PKA)-inhibitor Rp-8-Br-cAMPS. The islet hormone somatostatin inhibited the stimulatory action of GLP-I(7-36) amide and GIP via a cyclic AMP-independent mechanism, whereas insulin had no effect on exocytosis. These data suggest that the alpha-cells are equipped with receptors for GLP-I and GIP and that these peptides, in addition to their well-established insulinotropic capacity, also stimulate glucagon secretion. We propose that the reported inhibitory action of GLP-I on glucagon secretion is accounted for by a paracrine mechanism (e.g., mediated by stimulated release of somatostatin that in turn suppresses exocytosis in the alpha-cell).}}, author = {{Ding, W G and Renström, Erik and Rorsman, Patrik and Buschard, K and Gromada, J}}, issn = {{1939-327X}}, language = {{eng}}, number = {{5}}, pages = {{792--800}}, publisher = {{American Diabetes Association Inc.}}, series = {{Diabetes}}, title = {{Glucagon-like peptide I and glucose-dependent insulinotropic polypeptide stimulate Ca2+-induced secretion in rat alpha-cells by a protein kinase A-mediated mechanism}}, url = {{http://diabetes.diabetesjournals.org/cgi/content/abstract/46/5/792}}, volume = {{46}}, year = {{1997}}, }