LOCALIZATION OF AGE-RELATED-CHANGES IN NADPH-DIAPHORASE ACTIVITY IN PANCREATIC NEURONS

The distribution of NADPH-diaphorase activity in the pancreatic neuron s of neonatal, adult and aging rats was investigated using histochemis try. In the neonates, only 40% of the neuronal population showed NADPH -diaphorase labelling, and there was variation in the intensity of lab elling ranging from light to heavy staining. In the young and mature a dults, 95% of the neurons were labelled for NADPH-diaphorase activity, with most of the neurons being heavily labelled for the enzyme in the older animals. Immediately after birth, the pancreatic neurons found were small clusters of smaller sized cells compared with those observe d in the mature adults. Their number reached the adult level by the th ird month after birth; this was maintained throughout the mature adult phase and subsequently decreased in the aging rats.