title: Nitric oxide synthase immunoreactivity and NADPH-diaphorase activity in a subpopulation of intrinsic neurones of the guinea-pig heart.
abstract: This is the first report of the presence of nitric oxide synthase (NOS) immunoreactivity and NADPH-diaphorase (NADPH-d) activity in a subpopulation of the intrinsic neurones that innervate the heart. A cytochemical technique to detect NADPH-d and antisera raised against purified rat cerebellar NOS were employed to examine the expression of these enzymes by cells in a dissociated cell culture preparation from newborn guinea-pig atria and interatrial septum. Comparison of the results obtained by these two techniques and double-labelling experiments indicate that a subpopulation of intracardiac neurones contain both NADPH-d and NOS. These results indicate that some intracardiac neurones are capable of synthesizing nitric oxide. This raises the possibility that nitric oxide plays a role in the neural control of the heart.
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000032:analysis*; D000818:Animals; D000831:Animals, Newborn; D006168:Guinea Pigs; D006325:Heart Atria / Q000294:innervation; D006329:Heart Conduction System / Q000201:enzymology*; D006346:Heart Septum / Q000294:innervation; D009252:NADPH Dehydrogenase / Q000032:analysis*; D009474:Neurons / Q000201:enzymology; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase
chemical_list: D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D000594:Amino Acid Oxidoreductases; D009252:NADPH Dehydrogenase