Involvement of endogenous nitric oxide in the regulation of rat intestinal motility in vivo.
The effect of the nitric oxide (NO) synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME) on the motility of the small intestine in an acute model in the anaesthetised rat was determined by changes in jejunal intraluminal pressure. L-NAME (0.5-10 mg kg-1 i.v.) caused a dose-dependent increase in intraluminal pressure and initiated phasic intestinal contractions. These responses were inhibited by concurrent administration of L-arginine (200 mg kg-1 i.v.) but not by D-arginine (200 mg kg-1). The increase in jejunal motility induced by L-NAME was attenuated by atropine (4 mg kg-1), although even high doses of atropine (16 mg kg-1) did not abolish these responses. This indicates that although there are interactions between NO and muscarinic cholinergic mechanisms, other processes are also involved in these contractile events following administration of L-NAME. These observations in the rat suggest that endogenous NO plays a role in the modulation of intestinal motility in vivo.
Calignano
A
A
Wellcome Research Laboratories, Beckenham, Kent, UK.
Whittle
B J
BJ
Di Rosa
M
M
Moncada
S
S
D000818:Animals; D001120:Arginine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D001285:Atropine / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D005769:Gastrointestinal Motility / Q000187:drug effects; D007275:Injections, Intravenous; D007583:Jejunum / Q000187:drug effects / Q000502:physiology*; D008297:Male; D019331:NG-Nitroarginine Methyl Ester; D009569:Nitric Oxide / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D009569:Nitric Oxide; D001285:Atropine; D001120:Arginine; D019331:NG-Nitroarginine Methyl Ester