Constitutive nitric oxide modulates the injurious actions of vasopressin on rat intestinal microcirculation in acute endotoxaemia

Department of Pharmacology, Wellcome Research Laboratories, Beckenham, Kent, UK.
European Journal of Pharmacology (Impact Factor: 2.53). 09/1994; 260(2-3):265-8. DOI: 10.1016/0014-2999(94)90349-2
Source: PubMed

ABSTRACT The administration of the nitric oxide (NO) synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME, 5 mg/kg s.c.) concurrently with Escherichia coli endotoxin (3 mg/kg i.v.) increased vascular permeability and caused mucosal damage in the rat intestine 1 h later. The vasopressin V1 receptor antagonist, [Mca1,Tyr(Me)2, Arg8]vasopressin (0.01-0.2 microgram/kg s.c., 15 min before endotoxin) dose-dependently reduced this damage. These results suggest a beneficial role of NO, counteracting the injurious vascular actions of endogenous vasopressin, in maintaining intestinal mucosal integrity in acute endotoxaemic states.

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