Effects of nitric oxide synthase inhibitor in two-week oral treatment on hyperdynamic circulatory state in cirrhotic rats / 中国病理生理杂志

ABSTRACT

To investigate the effects of low dosage of nitric oxide synthase (NOS) inhibitor Nc-nitro -L-arginine methyl ester ( L-NAME) in two-week treatment on the hyperdynamic circulatory state in rats with cirrhosis. METHODS: Cirrhosis model was induced in male SD rats by injection of 60 % CCL4 oily solution subcutaneously. Cirrhotic rats were treated with L-NAME ( 0.5 mg·kg-1·d-1) by gavage for two weeks. Mean arterial pressure ( AP ), portal pressure(PP), cardiac output ( CO ), cardiac index ( CI ), splanchnic vascular resistance ( SVR ), splanchnic blood flow(SBF) and serum nitrite levels were determined in L-NAME-treated, L-NAME-untreated cirrhotic rats and controls by using 57Co-labled microsphere technique and a fluorometric assay, respectively. RESULTS: Untreated cirrhotic rats had significantly lower MAP, SVR and higher PP, CO, CI, SBF and nitrite concentration than those of the controls (all,P< 0.01 ). In treated cirrhotic rats, L-NAME significantly attenuated the increase of CO, CI, SBF, nitrite concentration and the decrease of MAP and SVR. In treated cirrhotic rats, L-NAME induced a marked decrease of nitrite concentration than untreated cirrhotic rats[(1.471±0.907)μmol/L vs (4.204±1.253) μmol/L, P<0.01]. CONCLUSION: The endogenous NO may play an important role in the changes of hemodynamics pattern in cirrhosis, and hyperdynamic circulatory state in rats with cirrhosis can be ameliorated by oral two-week administration of lower dose of L-NAME.