Insulin-Like Growth Factor-1 Receptor Is Differentially Distributed in Developing Cerebellar Cortex of Rats Born to Diabetic Mothers.

Insulin-like growth factor-1 (IGF-1) has an important role in development of the central nervous system (CNS). Maternal diabetes is associated with a higher risk of developmental abnormalities in their offspring including motor dysfunction and learning deficits. The present study aimed to investigate the effects of maternal diabetes on the distribution pattern of IGF-1 receptor (IGF-1R) in the developing rat cerebellar cortex. Wistar female rats were maintained diabetic from a week before pregnancy through parturition, and male offspring was killed at P0, P7, and P14. In spite of P0, there was a significant increase in the total cerebellar volume in the pups born to diabetic mothers. In diabetic group, the IGF-1R+ granular cell densities in internal granular (IGL) and molecular (ML) layers were increased at P0. Moreover, the number of positive granular and Purkinje cells in the IGL of diabetic neonates' cerebellum was reduced in comparison with the control group at P7 and P14. There were no differences either in volume or in the number of IGF-1R+ cells in the layers of the cerebellar cortex between the insulin-treated diabetic group and controls. Our data indicate that diabetes in pregnancy strikingly influence the localization of IGF-1R in the developing cerebellar cortex.