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 posthatching,
al1 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-diaphoraseINOS activity in the
pancreatic neurons is possibly correlated to the increase
in modulation of neurotransmission in the young chick