ISSN:
1573-2568
Keywords:
NITRIC OXIDE
;
SUPEROXIDE
;
SUPEROXIDE DISMUTASE
;
ESOPHAGUS
;
ESOPHAGEAL MOTILITY
;
SMOOTH MUSCLE
;
ENTERIC NERVOUS SYSTEM
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Nitric oxide mediates esophageal peristalsis andlower esophageal sphincter (LES) relaxation. Superoxideproduced with inflammation inactivates nitric oxide.Superoxide is cleared in biological systems by superoxide dismutase. We tested thehypothesis that superoxide and the superoxide scavengingsystem modulate LES function. Transverse strips ofmuscle from the opossum LES relaxed when stimulated by an electrical field. Diethyldithiocarbamite wasused to inhibit copper/zinc superoxide dismutase.Xanthine and xanthine oxidase were used to generatesuperoxide. Xanthine with xanthine oxidase ordiethyldithiocarbamite alone had no effect on the LES. However,xanthine/xanthine oxidase and diethyldithiocarbamitereduced LES relaxation 34.1% and increased its restingtone 71.2%. Superoxide dismutase did not affect LESfunction, but protected the tissue from the effects ofdiethyldithiocarbamite and xanthine/xanthine oxidase.These studies are consistent with the hypothesis thatsuperoxide acts by inactivating nitric oxide and suggest that these antioxidant enzyme systemsmay play a role in the maintenance of LESfunction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1018859428869
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