Involvement of nitric oxide in the inhibitory innervation of the human isolated colon

Autor: Guy E. Boeckxstaens, Arnold G. Herman, P.A. Pelckmans, Y. M. Van Maercke
Rok vydání: 1993
Předmět:
Zdroj: Gastroenterology
ISSN: 0016-5085
Popis: Background: The exact nature of the inhibitory nonadrenergic noncholinergic (NANC) neurotransmitter in the human colon is still unknown. Methods: The present study was designed to investigate the role of nitric oxide (NO) and adenosine 5′-triphosphate (ATP) in circular muscle strips of the human isolated colon. Results: NO and ATP induced tetrodoloxin-resistant relaxations that mimicked those evoked by nerve stimulation. Apamin inhibited the response to ATP, had a variable effect on the relaxations to transmural stimulation, and had no effect on those to NO or nitroglycerin. N G -nitro-l-arginine (l-NNA) concentration dependently reduced the NANC nerve-mediated relaxations, but had no effect on those to ATP, NO, or nitroglycerin; the l-NNA resistant part of the NANC relaxation to nerve stimulation was further reduced by apamin. The inhibitory effect of l-NNA or the combination of l-NNA and apamin was prevented by l-arginine but not by d-arginine. Conclusions: These results suggest that NO and another substance, perhaps ATP, are involved in the inhibitory NANC neurotransmission in the circulair muscle of the human colon.
Databáze: OpenAIRE