Abstract: | Functional and specific VIP receptors (relative potencies: VIP greater than PHI greater than secretin) have been characterized (cAMP generation) in enterocytes isolated from rat fetuses at 19 days gestation, after incubation at 37 degrees C in the presence of IBMX. In fetuses, VIP is about 6 times more potent (EC50 = 2.5 X 10(-10) M) than in adults (EC50 = 15 X 10(-10) M). This difference is not observed for PGE2, and is not related to cAMP-PDE activities (Km, Vmax). It is suggested that VIP may regulate the differentiation and function of enterocytes during the fetal life in rats. |