[Kinetics of insulin secretion in response to glucose by isolated islands of Langerhans from the fetal rat]

Abstract

Isolated islets of Langerhans from 21.5 day-old foetal Rats were studied in a perifusion system in vitro. The overall dynamics of insulin release by the foetal islets in response to glucose 13.9 mM is biphasic and qualitatively similar to that obtained with islets of adult Rats. The magnitude of the initial phase of insulin secretion is similar for the foetal and adult islets. The second phase is fourfold higher in the adult than in the foetus. The response of foetal islets occurs, 45 to 60 sec. after the increase of glucose concentration in the medium and a maximum insulin release for the first phase is obtained with a lag period of 2 min. The difference between foetal and adult islets is essentially quantitative.