Endocrine Rhythms: Roles of the Sleep-Wake Cycle, the Circadian Clock and the Environment
Diagnostic and Therapeutic Implications
40th International Henri-Pierre Klotz Symposium on Clinical Endocrinology
Paris, May 29-30, 1997
Guest Editors: G. Copinschi, Brussels; E. Van Cauter, Chicago, Ill.

Paper

Temporal Profiles and Clinical Significance of Pulsatile Insulin Secretion
Kenneth S. Polonsky, Jeppe Sturis, Eve Van Cauter

Department of Medicine, University of Chicago, Pritzker School of Medicine, Chicago, Ill., USA

Address of Corresponding Author

Horm Res 1998;49:178-184 (DOI: 10.1159/000023168)

  Key Words

• Insulin secretion
• Pulses
• NIDDM
• C-peptide
• Ultradian oscillations

  Abstract

In this article, recent experiments are reviewed which have addressed the role of oscillatory insulin secretion in the pathophysiology of glucose intolerance and diabetes. The ultradian oscillations of insulin secretion appear to be an integral part of the feedback loop between glucose and insulin secretion and as a result are abnormal in states of glucose intolerance. Treatment of impaired glucose tolerance with troglitazone, a thiazolidinedione that improves insulin sensitivity, leads to an improvement in the ability of the -cell to sense and respond to a glucose stimulus restoring the ability of glucose to entrain the ultradian oscillations. The rapid oscillations of insulin secretion appear to be an inherent feature of the cellular mechanisms of insulin secretion since they persist in the isolated perfused pancreas and in perifused islets. These oscillations are paralleled by changes in intracellular Ca²⁺ and are also abnormal in states of glucose intolerance and diabetes. Available evidence indicates that these alterations are due to decreased expression of voltage-dependent Ca²⁺ channels on the -cell membrane.

  Author Contacts

Kenneth S. Polonsky, MD
University of Chicago, Department of Medicine
5841 S. Maryland Avenue - MC1027
Chicago, IL 60637 (USA)
Tel. +1 773 702 6217, Fax +1 773 834 0486

  Article Information

Number of Print Pages : 7
Number of Figures : 4, Number of Tables : 0, Number of References : 20