OBJECTIVETo evaluate the effects of iNOS gene transfer on portal hypertensive rats.

METHODSEukaryotic expression plasmid pcDNA(3)/iNOS was used to transfect sinusoidal endothelial cells (SEC) mediated by Lipofectamine. Transfection rate and gene exspression were detected. Hepatic cirrhosis was induced in male Sprague-Dawley rats by intraperitoneal injection of carbon tetrachloride, and the cirrhotic rats were divided into three groups:Liposome-pcDNA(3)/iNOS (n = 10), Tris buffer (n = 10) and nude plasmid (n = 10), which were injected into the portal vein of experiment cirrhotic rats respectively. Five days later, animals were killed, immunohistochemistry and spectrophotometry methods were used to measure the expression of iNOS and the amount of NO production.

RESULTSEukaryotic expression plasmid pcDNA(3)/iNOS could effectively transfect SEC and express corresponding gene products. Following iNOS gene transfer, compared with the two controlled groups, iNOS expression and the NO production were significantly increased meanwhile portal pressure was decreased significantly.

CONCLUSIONSThe iNOS gene transfer is a feasible and an effective approach to treat portal hypertension in cirrhotic rats which could increase the expression of intra-hepatic iNOS and the amount of NO production thus leading to a remarkable reduction of portal venous pressure.