In Vitro Study of Insulin Secretion from Mouse Pancreatic Islets-Siriraj Experiences

Pancreatic islet isolation and culture technique are tools for direct investigation of the effects of substances on insulin secretion. Glucose is a well known insulin stimulating substance from the pancreatic islet. This study aims to demonstrate the first success (in Thailand) in islet isolation with intact insulin secretion from a mouse pancreas using collagenase P enzyme and histopaque separation. Isolated islets were cultured in RPMI 1640 for 24 hours before undergoing a glucose stimulation test. Glucose at five different concentrations (2.8, 5.6,10,15 and 20 mM) was used to demonstrate the dose-dependent response curve. Insulin secretion when stimulated with 5.6,10,15 and 20 mM glucose was higher than with 2.8 mM basal glucose concentration. Insulin secretion increased about 1.7 to 3.5 fold from a basal level of 2.8 mM glucose without any difference in insulin content at any glucose concentrations used. To our knowledge, these data demonstrate the first success in mouse pancreatic islet isolation and culture in Thailand. This technique can be used as a tool for further investigation of the in vitro effects of substances such as plants or new drugs on insulin secretion.