uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Insulin exocytosis and glucose-mediated increase in cytoplasmic free Ca2+ concentration in the pancreatic beta-cell are independent of cyclic ADP-ribose
Rolf Luft Center for Diabetes Research, Department of Molecular Medicine, Karolinska Institute, Karolinska Hospital, Stockholm, Sweden.
Swedish Medical Research Council.
Show others and affiliations
1996 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 271, no 32, 19074-19079 p.Article in journal (Refereed) Published
Abstract [en]

Stimulation of pancreatic beta-cells by glucose gives rise to an increase in the cytoplasmic free calcium concentration ([Ca2+]i) and exocytosis of insulin. Cyclic adenosine 5'-diphosphate ribose (cADPR), a metabolite of beta-NAD+, has been reported to increase [Ca2+]i in pancreatic beta-cells by releasing Ca2+ from inositol 1,4,5-trisphosphate-insensitive intracellular stores. In the present study, we have examined the role of cADPR in glucose-mediated increases in [Ca2+]i and insulin exocytosis. Dispersed ob/ob mouse beta-cell aggregates were either pressure microinjected with fura-2 salt or loaded with fura-2 acetoxymethyl ester, and [Ca2+]i was monitored by microfluorimetry. Microinjection of beta-NAD+ into fura-2-loaded beta-cells did not increase [Ca2+]i nor did it alter the cells' subsequent [Ca2+]i response to glucose. Cells microinjected with the cADPR antagonist 8NH2-cADPR increased [Ca2+]i in response to glucose equally well as those injected with cADPR. Finally, the ability of cADPR to promote exocytosis of insulin in electropermeabilized beta-cells was investigated. cADPR on its own did not increase insulin secretion nor did it potentiate Ca2+-induced insulin secretion. We conclude that cADPR neither plays a significant role in glucose-mediated increases in [Ca2+]i nor interacts directly with the molecular mechanisms regulating exocytosis of insulin in normal pancreatic beta-cells.

Place, publisher, year, edition, pages
1996. Vol. 271, no 32, 19074-19079 p.
National Category
Other Medical Sciences
URN: urn:nbn:se:uu:diva-132296DOI: 10.1074/jbc.271.32.19074PubMedID: 8702579OAI: oai:DiVA.org:uu-132296DiVA: diva2:357440
Available from: 2010-10-18 Created: 2010-10-18 Last updated: 2015-12-04Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Webb, Dominic-Luc
In the same journal
Journal of Biological Chemistry
Other Medical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 165 hits
ReferencesLink to record
Permanent link

Direct link