Patterns of glucose catabolism during differentiation of fetal rat epidermis.

Glucose metabolism has been investigated during differentiation of fetal rat skin to evaluate shifting patterns in the catabolism of this major exogenous substrate in relation to changing requirements during epidermal maturation. Glucose utilization and aerobic glycolysis declined while oxidative metabolism increased in whole skin as stratification and cornification progressed. Activity of the hexose monophosphate shunt was quantitated in isolated epidermis for the first time. The relative activity of this pathway diminished somewhat from 20% to 12% of utilized glucose as the granular layer and stratum corneum developed. The results are consistent with (a) enhanced utilization of glucose, aerobic glycolysis, and hexose monophosphate activity in rapidly proliferating eidermis, and (b) flexibility of glucose catabolism in response to cellular requirements at different stages of differentiation.