A-cell behavior in organ culture of isolated rat islets: secretion and tissue content of glucagon and insulin

Abstract

The present study was done to characterize the hormone secretion and content of isolated rat islets in organ culture dependent on the glucose concentration and the number of cultivated islets per culture bottle (10 or 30). For the calculation of the recovery rate the glucagon and insulin breakdown in the culture medium containing 10% calf serum was assayed. The glucagon recovery after incubation for 24 h at 37 degrees C varied from 2 to 92% and that of insulin from 75--105% depending on the serum batches. The cultivated islet responded to 16 mmol glucose by a significant enhancement of insulin release, whereas the glucagon release was not influenced. The glucagon release fell progressively with the duration of cultivation. 2 mmol dibutyryl cyclic AMP augmented insulin and glucagon release in the presence of 5 and 16 mmol glucose and significantly enhanced the glucagon content in the cultivated islets.