help button home button Endocrine Society Endocrinology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS

This Article
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Reusch, J. E.
Right arrow Articles by Draznin, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Reusch, J. E.
Right arrow Articles by Draznin, B.

Endocrinology, Vol 129, 3269-3273, Copyright © 1991 by Endocrine Society


ARTICLES

Regulation of GLUT-4 phosphorylation by intracellular calcium in adipocytes

JE Reusch, N Begum, KE Sussman and B Draznin
Medical Research Service, Veterans Affairs Medical Center, Denver, Colorado 80220.

Sustained elevations in cytosolic calcium concentrations ([Ca2+]i) have been shown to render insulin target cells resistant to insulin action. In this study we examined the mechanisms of the detrimental effect of high levels of [Ca2+]i on insulin-induced 2-deoxyglucose (2-DOG) uptake. To elevate [Ca2+]i, we incubated rat adipocytes with either 40 mM potassium (K+) or 20 ng/ml PTH for 1 h for in vitro experiments and injected rats with PTH (injections of 50 micrograms, ip, every hour for 3 h) for in vivo studies. Adipocytes with elevated [Ca2+]i demonstrated a 30% decrease in insulin-stimulated 2-DOG uptake. A calcium channel blocker (nitrendipine) and a cAMP antagonist (RpcAMP) each partially restored insulin-stimulated glucose transport, but together they completely restored 2-DOG uptake. Concomitantly, we found a significant increase in phosphorylation of GLUT-4 in adipocytes with elevated [Ca2+]i. This change in GLUT-4 phosphorylation was also attenuated by nitrendipine and RpcAMP. These observations confirm that elevated [Ca2+]i diminishes insulin-stimulated glucose transport and suggest that increased phosphorylation of GLUT-4 in adipocytes with high [Ca2+]i may alter its intrinsic activity.


This article has been cited by other articles:


Home page
J. Clin. Endocrinol. Metab.Home page
A. G. Pittas, J. Lau, F. B. Hu, and B. Dawson-Hughes
The Role of Vitamin D and Calcium in Type 2 Diabetes. A Systematic Review and Meta-Analysis
J. Clin. Endocrinol. Metab., June 1, 2007; 92(6): 2017 - 2029.
[Abstract] [Full Text] [PDF]


Home page
JAMAHome page
M. F. McCarty, G. Merzer, M. A. Pereira, and D. S. Ludwig
Dairy Products and Insulin Resistance
JAMA, August 14, 2002; 288(6): 693 - 694.
[Full Text] [PDF]


Home page
Am. J. Physiol. Endocrinol. Metab.Home page
J. R. Levy, J. Gyarmati, J. M. Lesko, R. A. Adler, and W. Stevens
Dual regulation of leptin secretion: intracellular energy and calcium dependence of regulated pathway
Am J Physiol Endocrinol Metab, May 1, 2000; 278(5): E892 - E901.
[Abstract] [Full Text] [PDF]




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals
Copyright © 1991 by The Endocrine Society