Effects Of Splenic Artery Ligation On Liver Regeneration After Partial Hepatectomy In Rats

Background and Objective Liver cancer is one of the common malignant tumors in our country.In the treatment of liver malignancies,surgeons often face the dilemma between radical resection of tumor and preservation of residual liver function.This concern often causes the surgeon to abandon the radical resection of the tumor.Therefore,how to improve the capacity of liver regeneration after partial liver resection has become an urgent problem to be solved.Studies have shown that splenectomy promote liver regeneration after partial hepatectomy in rats.Compared with splenectomy,splenic artery ligation can also reduce the blood flow to the portal vein,reduce portal pressure,ease the portal high perfusion state after liver resection.And the operation is simple and easy to undergo,the incision is relatively small,relatively shorten the time of operation,reduce intraoperative bleeding and the risk of surgery,while retaining the immune function and clear function of the spleen,and so on.But the effect and the mechanism of splenic artery ligation on liver regeneration remain unclear.In this study,70% hepatectomy model of Sprague-Dawley rats was established to observe the effect of splenic artery ligation on liver function recovery and the expression of HGF ?TGF-? and TGF-?1,to explore the effect of splenic artery ligation on liver regeneration.Materials and Methods Preliminary experiments were carried out to establish a stable 70% liver resection model in rats.On the basis of this,72 healthy male Sprague-Dawley rats(purchased from Experimental Animal Center of Henan Province),6-8 weeks old,weighing 220-250 g,were randomly divided into 3 groups,the sham operation group(A group):after laparotomy,only the left and middle lobes of the liver were separated,and 1.5cm from splenic hilum,the splenic vein and splenic artery were separated.;70% liver resection group(group B): complete resection of the left hepatic lobe and middle lobe of liver in rats;70% liver resection + splenic artery ligation group(group C): after resection of the left and the middle lobe of the rat liver 1.5cm from the hilum of the spleen,ligate the splenic artery,after resection of the left and middle lobes of the liver.Each group was divided into three stages: 24 h,48h and 72 h after surgery,weighing,laparotomy and take abdominal aorta blood after anesthesia and take liver specimens.The weight of the rats before anesthesia was recorded and the wet weight of the liver was measured.The ratio of liver weight and body weight of the rats was calculated.The blood of the abdominal aorta was collected and the biochemical indexes ALT and AST were measured.The HGF,TGF-? and TGF-?1 of serum were measured by enzyme-linked immunosorbent assay(ELISA);The liver tissues fixed by the polyformaldehyde and the expressions of TGF-? and TGF-?1 in liver tissue were detected by immunohistochemical method.SPSS 21.0 software was used to analyze the differences among the indexes.The difference was statistically significant with P<0.05.Results70% hepatectomy model of SD rats was successfully established.Rats were able to survive normally during the experiment.The ratio of liver to body in group B and group C increased gradually with time.Compared with group B,the ratio of liver to body was smaller in group C at 24 h after operation(P<0.05).There was no significant difference between the two groups in the ratio of liver to body at 48 h after operation(P>0.05).It was increased in group C at 72 h after operation(P<0.05).Compared with group A,the levels of serum ALT and AST were significantly increased in group B and group C at 24,48 and 72 h after the operation(P<0.05).The levels of ALT and AST in group B and group C decreased gradually with time.The levels of ALT and AST in group C were lower than those in group B at 24,48 and 72 h after the operation(P<0.05).Compared with group A,the levels of TGF-? in the serum and the expression of TGF-? in liver tissue were significantly increased in group B and group C at 24,48 and 72 h after operation(P<0.05).Compared with group B,the levels of TGF-? in the serum and the expression of TGF-? in liver tissue were increased in group C at 24 h after the operation(P<0.05).There was no significant difference in the levels of TGF-? in the serum and in the expression of TGF-? in liver tissue 48 and 72 h after the operation between the two groups(P> 0.05).Compared with group A,the expression of TGF-?1 in liver tissue in group B and group C increased significantly at 24,48 and 72 h after the operation(P<0.05).Compared with group B,the expression of TGF-?1 in liver tissue in group C was not significantly different at 24,48 and 72 h after the operation(P>0.05).The levels of TGF-?1 in serum of group B were higher than those of group C at24,48 and 72 h after the operation(P<0.05).There was no significant difference in the level of HGF in serum between group B and group C at 24,48 and 72 h after the operation(p> 0.05).Conclusions1.Splenic artery ligation can reduce liver injury,improve the speed of the quality of residual liver to increase and promote the recovery of liver function in the 70%liver resection rats;2.Ligation of splenic artery can promote the expression of TGF-? at 24 h in 70%hepatectomy rats,suggesting that splenic artery ligation promote liver regeneration in early(24h)after 70% liver resection in rats;3.Ligation of the splenic artery reduced the level of TGF-?1 in serum at 24,48 and72 h after the operation of 70% liver resection,suggesting that splenic artery ligation may indirectly promote the regeneration of liver by reducing the level of TGF-?1 in serum after 70% liver resection in rats.