The cytoplasmic Ca2+ response to glucose as an indicator of impairment of the pancreatic beta-cell function

European Journal of Clinical Investigation
B HellmanP E Lund

Abstract

The effects of glucose on the cytoplasmic Ca2+ concentration (Ca2+i) regulating insulin release were investigated using pancreatic beta-cells representative for the normal and diabetic situations. Increase of the glucose concentration resulted in a slight lowering of Ca2+i followed by a rise, often manifested as high amplitude oscillations. The Ca2+i-lowering component in the glucose action associated with suppression of insulin release became particularly prominent when the beta-cells were already depolarized by tolbutamide. Glucose-induced inhibition of insulin release was observed also in experiments with rats made diabetic with streptozotocin or alloxan. Other studies indicated lowering of plasma insulin after intravenous glucose administration in patients with insulin- and noninsulin-dependent diabetes mellitus. Brief exposure of beta-cells to 2.2 mmol l-1 streptozotocin resulted in impairment of the response to glucose, manifested as disappearance of the cyclic variation of Ca2+i. The results indicate that glucose-induced depolarisation is a vulnerable process, the disturbance of which may contribute to insulin secretory defects in diabetes mellitus.

References

May 1, 1979·The Journal of Clinical Endocrinology and Metabolism·S A MetzR P Robertson
Jan 15, 1988·Biochemical and Biophysical Research Communications·E GrapengiesserB Hellman
Mar 30, 1988·Biochemical and Biophysical Research Communications·E GrapengiesserB Hellman
May 12, 1988·The New England Journal of Medicine·S O'RahillyD R Matthews
Aug 31, 1987·Biochemical and Biophysical Research Communications·H JohanssonB Hellman
Oct 8, 1965·Annals of the New York Academy of Sciences·B Hellman

❮ Previous
Next ❯

Citations

Jun 27, 2000·Diabetes/metabolism Research and Reviews·P Bergsten
Dec 8, 2009·Upsala Journal of Medical Sciences·Bo Hellman
Jun 16, 2005·American Journal of Physiology. Endocrinology and Metabolism·James T TaylorMing Li
Mar 24, 2005·American Journal of Physiology. Endocrinology and Metabolism·Géraldine ParnaudDomenico Bosco

❮ Previous
Next ❯

Related Concepts

Related Feeds

Biomarkers for Type 2 Diabetes

Biomarkers can help understand chronic diseases and assist in risk prediction for prevention and early detection of diseases. Here is the latest research on biomarkers in type 2 diabetes, a disease in which the body is unable to produce or properly use insulin.

Autoimmune Diabetes & Tolerance

Patients with type I diabetes lack insulin-producing beta cells due to the loss of immunological tolerance and autoimmune disease. Discover the latest research on targeting tolerance to prevent diabetes.