Experimental Study Of The Effect Of External Biliary Drainageon On The Obstructive Jaundice Rats Modle And Liver Regeneration

Objective: To research the effect of different degrees of biliary drainage on obstructive jaundice rats and liver regeneration after hepatectomy, providing a theoretical basis for the preoperative biliary drainage to hilar cholangiocarcinoma.Methods: Builting the external biliary drainage animal model(obstruct 10 days), we divided all rats in four groups according to different drainaging times. 1, SO-Hx group: Normal rat hepatectomy group; 2, ED0-Hx group: External biliary drainage 0 days hepatectomy group; 3, ED2-Hx group: External biliary drainage 2 days hepatectomy group; 4, ED10-Hx group: External biliary drainage 10 days hepatectomy group. Observe the mortality of rats 15 days later,the liver functional rehabilitation and the ratio of residual liver weight/rat weight 7 days later. Detect the peak expression of PCNA and HGF mRNA in residual hepatic tissue by immunohistochemistry and RT-PCR technology.Results: (1), The mortality in ED0-Hx group was very high(up to 40 percent), significantly higher than that in SO-Hx Group (0 percent). The mortality in ED2-Hx and ED10-Hx group decreased significantly, to 20 percent and 5 percent, but still higher than the SO-Hx group. (2), The total bilirubin level in ED0-Hx group was highest at 0h and still about 10 times higher than that in SO-Hx group 168h (7 days)later, the difference between the two groups were statistically significant (p<0.05) ; Aspartate aminotransferase also increased significantly and the recovery process was simillar to total bilirubin. Although the total bilirubin level in ED2-Hx group has dropped substantially at 0h, but the recovery process is similar to ED0-Hx groups. 168 h (7 days) later the total bilirubin still about 5 times higher than the that in SO-Hx group, the difference between the two groups were statistically significant (p <0.05); The total bilirubin and aspartate aminotransferase in ED10-Hx group are in a normal level during the 168h (7 days) after hepatectomy, Compared to the SO-Hx group there was not statistically difference (p>0.05). (3). The ratio of residual liver weight / rat weight 7 days after hepatectomy in SO-Hx was highest. Residual liver proliferation in the drainage groups significantly weakened, comparing to SO-Hx group the differences were statistically significant (p <0.05). Residual liver proliferation in ED2-Hx group was higher than that in ED0-Hx group and in ED10-Hx group it was highe than that in ED0-Hx group and ED2-Hx groups, comparing to eath other the differences were statistically significant(p<0.05). (4), The peak expression of PCNA and HGF mRNA increased after the external biliary drainage. The peak expression of PCNA and HGF mRNA in the external biliary drainage groups were lower than that in SO-Hx group, the differences were statistically significant (p<0.05). The peak expression of PCNA and HGF mRNA in ED2-Hx group was higher than that in ED0-Hx group, The peak expression of PCNA in ED10-Hx group was higher than that in ED2-Hx group, the differences between eath other were statistically significant (p <0.05).Conclusion: 1. The hyperbilirubinemia caused by Biliary obstruction significantly inhibited the liver regeneration. liver function improved after external biliary drainage and the condition gradually recovered. Rat mortality reduced. 2. Although liver function inproved greatly in a short time after external biliary drainage, the liver regeneration was still in the inhibiting condition, the mortality was still high that was not suitable for the surgery. 3. It should be a long time drainage and after the liver function had been restored completely that the surgery for expanding hepatectomy can be safe.