OBJECTIVETo investigate the action of nitric oxide (NO) on testicular dysfunction in cirrhotic rats.

METHODSCirrhotic rats were induced by bile duct ligation (BDL). Concentration of NO in the serum and homogenates of the testicular tissue in biliary cirrhotic rats, L-NAME rats, and sham operated rats were measured by assay of nitrate reductase. Concentrations of testosterone in the serum of 3 groups were measured by radioimmunoassay. Sperm density and percent of motive sperm in the epididymis of the rats were determined.

RESULTSConcentrations of NO in the serum and homogenates of the testicular tissue of cirrhotic rats were significantly greater than those of sham operated rats (4.165 micromol/L 1.162 micromol/L, and 1.305 micromol/g 0.087 micromol/g vs 0.535 micromol/L 0.237 micromol/L and 0.720 micromol/g 0.063 micromol/g). Concentrations of testosterone in the serum, the sperm density and percent of motive sperm in the epididymis were significantly lower in cirrhotic rats than sham operated rats (0.049mug/L 0.020 microgram/L, 16.46% 4.84%, and 86.89 10(6)/ml 33.17 10(6)/ml vs 2.680 microgram/L 0.403 microgram/L, 62.45% 9.21%, and 299.43 10(6)/ml 53.85 10(6)/ml). By contrast, the administration of a low dose of L-NAME (0.5 mg/kg per day) for one week to cirrhotic rats was associated with a significant reduction in concentration of NO (1.975 micromol/L 0.406 micromol/L and 0.950 micromol/g 0.057 micromol/g) and a significant increase in concentration of testosterone in the serum, the sperm density and percent of motive sperm in the epididymis (0.993 microgram/L 0.179 microgram/L, 33.85% 4.93%, and 188.94 10(6)/ml 38.34 10(6)/ml).

CONCLUSIONSNO is associated with testicular dysfunction in cirrhosis. The testicular dysfunction induced by cirrhosis can obtain improvement by using low dose of L-NAME.