Protective effects of vasoactive intestinal peptide on septic shock rats / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the protective effects of vasoactive intestinal peptide (VIP) on septic shock rats and explore its possible mechanism.</p><p><b>METHODS</b>Cecal ligation and puncture (CLP) was performed to produce septic shock rat model. Thirty adult Sprague-dawley rats were randomly divided into 3 groups with 10 animals in each group: sham operation group, CLP group and VIP group. The rats in VIP group were given intravenous injection of VIP (5 nmol per rat) instantly after the CLP operation. Then the mean arterial pressure (MAP) was monitored consistently and survival rate was observed. Blood samples were obtained from femoral artery for measuring the serum concentrations of tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) by using enzyme-linked immunosorbent assays (ELISA). Organs (lung, kidney and intestine) were harvested for pathological examination.</p><p><b>RESULTS</b>At each time point after 8 h, the MAP of VIP rats was significantly higher than that in CLP rats (P<0.05). In VIP group rats, the serum TNF-alpha concentration was decreased meanwhile IL-10 level was increased with markedly alleviated organic pathological injuries and the survival rate was obviously raised.</p><p><b>CONCLUSIONS</b>VIP exerts protective effects on septic shock rats through inhibiting production of proinflammatory factors and stimulating the production of anti-inflammatory cytokines.</p>

Experimental study on iNOS gene transfer mediated by liposome to treat portal hypertension in cirrhotic rats / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the effects of iNOS gene transfer on portal hypertensive rats.</p><p><b>METHODS</b>Eukaryotic 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.</p><p><b>RESULTS</b>Eukaryotic 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.</p><p><b>CONCLUSIONS</b>The 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.</p>