Nitric oxide production is diminished in colonic circular muscle from acquired megacolon. Dis Colon Rectum 2000 Jun;43(6):821-8
Date
06/20/2000Pubmed ID
10859084DOI
10.1007/BF02238021Scopus ID
2-s2.0-0034082082 (requires institutional sign-in at Scopus site) 8 CitationsAbstract
PURPOSE: Nitric oxide modulates human colonic smooth muscle function. To determine whether nitric oxide production is altered in colon from acquired megacolon, we measured cholinergic nerve-mediated contractions in vitro before and after inhibition of nitric oxide synthase.
METHODS: Intramural nerves in circular smooth muscle from histologically normal colon (n = 12) and acquired megacolon (n = 3) were activated by electrical field stimulation.
RESULTS: In controls blockade of nitric oxide synthase by N(G)-Nitro-L-Arginine induced increases (P < 0.05) in amplitude of contractions; these increases in amplitudes were blocked by L-Arginine (analysis of variance; P < 0.05). By contrast, blockade of nitric oxide synthase did not increase amplitudes of contractions with circular smooth muscle from acquired megacolon. An immediate phasic contraction was blocked by atropine sulfate.
CONCLUSIONS: The results support the concept that nitric oxide production modulates cholinergic nerve-mediated contractions in normal colonic circular muscle, whereas acquired megacolon is associated with altered release of this inhibitory neurochemical. Potential explanations include depletion of tissue L-Arginine, decreased capacity to recycle citrulline to arginine, or decreased release of vasoactive intestinal peptide from circular smooth muscle in acquired megacolon.
Author List
Koch TR, Otterson MF, Telford GLAuthor
Mary F. Otterson MD Professor in the Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AgedAged, 80 and over
Colon
Electric Stimulation
Female
Humans
Male
Megacolon
Middle Aged
Muscle, Smooth
Nitric Oxide
Nitric Oxide Synthase
