Localization of NADPH-diaphorase activity in the pancreatic ganglia of the young chick.

NADPH-diaphorase activity was localized in pancreatic ganglia of the young chick. At 1 day posthatching, 60% of the neurons in the pancreatic ganglia were NADPH-diaphorase positive. In each neuron, the NADPH-diaphorase labelling was localized mainly in the cytoplasm of the cell body and its proximal processes, but not in the cell nucleus. There was a gradation in the labelling for the enzyme, with some neurons being heavily labelled while others were lightly to moderately labelled. At 7 days post-hatching, 100% of the pancreatic neurons showed NADPH-diaphorase activity and the average size of the NADPH-diaphorase positive neurons had also increased. By 14 days post-hatching, all the neurons present were heavily labelled for NADPH-diaphorase activity. Some of the labelled nerve processes traversed long distances and finally terminated on other ganglia as well as on the exocrine acinar or endocrine cells. It is concluded that this increase in NADPH-diaphorase/NOS activity in the pancreatic neurons is possibly correlated to the increase in modulation of neurotransmission in the young chick.