Stimulation of insulin secretion reveals heterogeneity of pancreatic B cells in vivo

J Clin Invest. 1987 Jul;80(1):175-83. doi: 10.1172/JCI113045.

Abstract

We examined the immunofluorescence and ultrastructural changes of insulin-producing B cells in the center and at the periphery of islets of Langerhans during in vivo stimulation by glucose and glibenclamide. A decreased insulin immunostaining was detected in islets from the splenic rat pancreas after 1.5 h of glucose stimulation. By contrast, immunofluorescence changes became apparent in islets from the duodenal pancreas only after greater than 3 h of hyperglycemia. In both cases, the immunolabeling of central B cells decreased before that of peripheral B cells. Similar changes were seen following in vivo stimulation of insulin secretion by glibenclamide. At the ultrastructural level, hyperglycemia decreased the volume density of B cell secretory granules and increased that of rough endoplasmic reticulum and Golgi apparatus. These changes were also detected earlier in central than in peripheral B cells and earlier in splenic than in duodenal islets. The data show that B cells form a heterogeneous population in vivo.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cytoplasmic Granules / ultrastructure
  • Endoplasmic Reticulum / ultrastructure
  • Fluorescent Antibody Technique
  • Glucose / pharmacology
  • Glyburide / pharmacology
  • Golgi Apparatus / ultrastructure
  • Insulin / metabolism*
  • Insulin Secretion
  • Islets of Langerhans / drug effects
  • Islets of Langerhans / metabolism*
  • Islets of Langerhans / ultrastructure
  • Male
  • Microscopy, Electron
  • Rats
  • Rats, Inbred Strains

Substances

  • Insulin
  • Glucose
  • Glyburide