RESUMO
Objective To study the effects of nitric oxide (NO) and endothelin-1(ET-1) on cholestasis liver fibrosis. Methods Forty-eight Wistar rats were randomily divided into 3 groups:the control group,the common bile dute ligation(CBDL)group,and the CBDL plus lactulose group.The animals were killed on the 3rd,7th,14th, and 21th days respectively to determine the contents of plasma endotoxin,NO,ET-1, and transaminases(ALT,AST).The degree of hepatic fibrosis was observed by microscopy and the ultrastructural changes of liver were observed by electron microscope. Results After common bile dute ligation,the contents of plasma ET-1 and NO increased significahtly,the plasma endotoxin level also increased and there were positive correlation between the levels of ET-1,and NO and the level of endotoxin.Plasma transaminases also increased greatly compared with those of the control group.The hepatic sinusoidal steonsis and widen Disse space were found.The diameter and number of fenestrate on hepatic sinusoid greatly decreased.Treatment with lactulose could partially alleviate all the pathological changes noted above. Conclusions NO and ET-1 may damage the "liver sieve"to cause the cholestasis liver fibrosis.