Role of nitric oxide-related inhibition in intestinal function: relation to vasoactive intestinal polypeptide

This study examined the role of nitric oxide (NO) in tonic inhibition of motor activity in isolated, perfused canine ileal segments. Brief addition of N omega-nitro-L-arginine methyl ester (L-NAME) to the perfusate caused, after a delay, a concentration-dependent persistent increase in tonic and phasic activity of circular muscle. This increased motor activity was prevented or reversed by addition of L- but not D-arginine to the perfusate. …