Experiment On The Effects Of PNS To Prevent The Ischemia-Reperfusion Injury Of Donors' Bile Duct In The Model Of Rabbit's Orthotopic Piggyback Liver Transplantation

Objective: To prove the effects and mechanisms of PNS to prevent the ischemia-reperfusion injury of donors' bile duct in the model of rabbit's orthotopic piggyback liver transplantation.Methods: Build up the model of rabbit's orthotopic piggyback liver transplantation with 36 cases, 81 rabbits were randomly divided into three different groups: normal saline control group(group NS), PNS preconditioning group(group PNS) and sham-operated group(group SO) and carry out a randomly controlled experiment toward the receptor. The project on group NS is to input 5 ml NS from the vein on the ear of donor for three days before the operation, once time every day. To group PNS, we take the similar methods, but the only difference is the 5 ml fluid including PNS and NS, the dose of PNS is 60mg for the per kilogram weight of donor. For group SO, we do nothing before the operation, and what we do during the operation is just opening abdominal cavity and dissociating liver and carefully ligating the vein under left diaphragm and right adrenal gland vein. Obtaining the bile duct tissue of every group as specimen after killing the animals on every group according to 2h ,6h and 24h after reperfusion respectively. To understand the effects of PNS to prevent the ischemia-reperfusion injury of donors' bile duct in the model through detecting the change of bile duct tissue pathology including the largest diameter and area of mitochondria and the apoptosis and necrosis rates of cells on bile duct tissue.Results: After the operation of liver transplantation, the bile duct tissue of group SO in 2h ,6h and 24h after reperfusion and that of group PNS in 24h almost have no damage according to the results of microscope and electron microscope . Compared with the largest diameter of mitochondria of group SO, that of group NS in 2h,6h after reperfusion and that of group PNS in 2h are significantly larger than that of group SO (P < 0.01), that of group NS in 24h and that of group PNS in 6h are larger than that of group SO (P < 0.05 ) ,that of group PNS in 2h,6h and 24h is smaller than that of NS group(P < 0.05 ). The largest area of mitochondria of group NS and group PNS in 2h are all larger than that of group SO, that of group NS in 6h and 24h are significantly larger than that of SO group (P < 0.01), that of group PNS in 6h and 24h are smaller than that of NS group (P < 0.05) , the largest diameter and area of mitochondria of group NS and group PNS are the largest in 6h . The apoptosis rates of cells on bile duct tissue of group NS and group PNS in 2h are larger than that of group SO (P < 0.05 ) , that of the two groups in 6h and 24h are significantly larger than that of group SO (P < 0.01), that of group PNS in 2h and 6h are smaller than that of group NS (P < 0.05), that of group PNS in 24h is significantly smaller than that of group NS (P < 0.01). The necrosis rates of cells on bile duct tissue of group NS and group PNS in 2h,6h and 24h are significantly larger than that of group SO (P < 0.01) , that of group PNS in 6h is significantly smaller than that of group NS (P < 0.01) and that in 24h is smaller than that of group NS (P < 0.05 ) .The total necrosis rates of cells on bile duct tissue of group NS and group PNS in 2h and 6h are significantly larger than that of group SO (P < 0.01) , that of group PNS in 2h and 6h are significantly smaller than that of group NS (P<0.01) .Conclusion: The PNS may educe the effects of protecting the normal shape and function of mitochondria on bile duct tissue through the mechanism of playing anti-inflammatory, cleaning oxygen-derived free radicals and maintaining the balance of homeostasis of calcium, so it can effectively prevent the ischemia-reperfusion injury of donors' bile duct.