AJP - Endocrinology and Metabolism, Vol 263, Issue 5 E890-E896, Copyright © 1992 by American Physiological Society

ARTICLES

Glucose-induced insulin release in islets of young rats: time-dependent potentiation and effects of 2-bromostearate

C. R. Bliss and G. W. Sharp
Department of Pharmacology, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853.

The development of glucose-stimulated insulin release and time-dependent potentiation (TDP) has been studied in isolated islets from 7-, 14-, and 21-day-old and 3-mo-old rats. Responses were small at 7 days and changed little at 14 days. At 21 days the amount of insulin released in response to glucose was two times that at 14 days but was still less than one-half that released by 3-mo islets. Glucose-induced TDP was absent at 7 days but was present at 21 days. The second phase response to glucose decreased with perifusion time in 7-, 14-, and 21-day islets. In 7- and 21-day islets, high glucose in the presence of 2-bromostearate, an inhibitor of fatty acid oxidation, prevented the time-dependent decrease in responses; in addition, it induced TDP and enhanced TDP in the 7-day and 21-day islets, respectively. The data suggest that, in the young islet, glucose metabolism fails to inhibit fatty acid oxidation as it does in the mature islet and that this leads to a diminished signal for stimulus-secretion coupling.

This article has been cited by other articles:

				Y.-J. Liu, H. Cheng, H. Drought, M. J. MacDonald, G. W. G. Sharp, and S. G. Straub Activation of the KATP channel-independent signaling pathway by the nonhydrolyzable analog of leucine, BCH Am J Physiol Endocrinol Metab, August 1, 2003; 285(2): E380 - E389. [Abstract] [Full Text] [PDF]