Effects Of Splenectomy On Liver Regeneration After Repeated Liver Resection In Rats

[Objective] To establish a rat model of repeated hepatectomy and to investigate the effects of splenectomy on liver regeneration after repeated hepatectomy.[Methods] Part1:To establish a rat model of repeated hepatectomy:A70%repeated hepatectomy rat model was established after7days of the first70%hepatectomy. Part2:to investigate the features and the effects of splenectomy on liver regeneration after repeated hepatectomy in rats.60male wistar rats weighing230-270g, were randomly divided into three groups. Group A underwent70%hepatectomy, group B underwent70%hepatectomy after7days of first hepatectomy, group C combined splenectomy simultaneously at the second hepatectomy.5rats of each group were randomly sacrificed at day1,3,5and7after operation. Portal venous pressure was monitored at each time point of sacrificing,5ml of blood sample from the inferior vena cava was obtained, part of the blood sample was used to count platelet number, other part was centrifuged and stored in order to detect liver function, HGF and TGF-β1. Liver tissue was obtained, weighed to calculate the liver to body ratio, some of the tissue was fixed by formaldehyde for HE staining and immunohistochemical staining (liver cells proliferating nuclear antigen, PCNA). Results were analyzed using SPSS16.0statistical analysis software.[Results] A rat model of repeated hepatectomy was established. The difference of portal vein pressure at different time points and with different intervention methods is statistically significant. The comparison between groups showed the pressure was significantly higher in group B than in group A and C (P<0.05) on day1and3. The difference of liver to weight ratio at different time points and with different intervention methods is statistically significant. The comparison between groups showed the ratio was significantly higher in group A than in group C (P<0.05), and group C was higher than group B on day1(P<0.05), on the third day, the ratio in group A and C were higher than in group B (P<0.05). The difference of ALT at different time points and with different intervention methods is statistically significant. The comparison between groups showed the level of ALT was lower in group A and C than in group B on day1(P<0.05). The difference of AST at different time points and with different intervention methods is statistically significant. The comparison between groups showed the level of AST was lower in group A and C than in group B on day1and3(P<0.05). The difference of TBIL at different time points and with different intervention methods is statistically significant. The comparison between groups showed the level was lower in group A and C than in group B on day1(P<0.05). The difference of platelet count at different time points is not statistically significant and the difference of intervention methods is statistically significant. The comparison between groups showed there was no difference between groups. The difference of PCNA at different time points and with different intervention methods is statistically significant. The comparison between groups showed the index was higher in group A and C than in group B on day1(P<0.05). The difference of HGF at different time points and with different intervention methods is statistically significant. The comparison between groups showed the level was higher in group A than in group C (P<0.05) and group C was higher than group B on day1(P<0.05), on day3, the level was lower in group A and C than in group B (P<0.05). The difference of TGF-β1at different time points and with different intervention methods is statistically significant. The comparison between groups showed the level of TGF-β1was lower in group A and C than in group B on day1(P<0.05), and the level was higher in group A and B than in group C on day3(P<0.05).[Conclusions]1. A stable model of repeated hepatectomy in rats can be established;2. Compared with the first hepatectomy, the liver regeneration of repeated hepatectomy rats was delayed, but the long-term regeneration ability was nomal;3. The function and regeneration of the liver was superior in rats underwent repeated hepatectomy combined with splenectomy than those underwent single repeated hepatectomy.