Fetal Rat Pancreas in Organ Culture: Effect of Exogenous Insulin on the Development of the Islet Cells

Abstract

Explants of 18 day postcoitum fetal rat pancreas were grown in organ culture for four days in a tissue culture medium with or without supplementation with porcine insulin (1 μg/ml). Explants cultured in the presence of added insulin had a greater beta cell volume and a greater insulin content than those grown without added insulin. In addition, the explant delta cell volume and somatostatin content were reduced in the explants supplemented with insulin. There was no effect of exogenous insulin on the alpha cell volume or the glucagon content of the explants. These findings suggest that the hypertrophy of the islets observed in several experimental model systems and in human disease states may be related to the elevation in the concentration of circulating insulin which usually accompanies the islet hypertrophy.