Since The Experimental Study Of The Transplantation Of Splenic Blood Vessels Nerve Regeneration

Objective: To study the process of regeneration of blood vessels and nerves in splenic autotransplants and analyze the regulatory effects of VEGF and KDR on vascular regeneration in autotransplanted spleen. Methods: One hundred and forty healthy Wistar rats were equally divided into seven groups. In each group, splenectomy and splenic autotransplantation were performed in fifteen animals, the other five only had sham-operation. The following investigations were conducted 7, 14, 30, 60, 90, 120 and 180 days later in each group: (1) Pathological changes of splenic autotransplants were investigated under light microscope and transmission electron microscope. (2) Density changes of renascent blood vessels after splenic autotransplantation were studied under light microscope and through computer image analysis qualification twenty four hours after the perfusion of chinese ink into aorta. (3)Regeneration process and density changes of the NPY positive nerve fibers iii splenic autotgrafts were studied by immunohistochemical methods and computer image analysis qualification. (4)VEGF and KDR positive cells were showed by immunohistochemical methods. Computer image analysis qualification was used to analyze their density changes. Results: (1)After the pathological course of acute phase, remissive phase and renovate phase, splenic autotransplants could regain their structure and function. (2)Seven days after operation, we could see the renascent blood vessels extended from greater omentum into splenic autografts. With the time going on the vacular density in autografts become greater. One hundred and eighty days after operation, the density almost became normal.(3)The NPY positive nerve fibers began their regeneration thirty days after operation and extended from greater omentum into splenic autotransplants. Density of the nerve fibers gradually became greater and almost normal one hundred and eighty days after operation. (4)Density of VEGF and KDR positive cells rose quickly seven days after operation. The peak density was noted sixty days after operation and gradually decreased to normal level one hundred and eighty days after operation. Conclusion: Autotransplantation of spleen into greater omentum is a convenient and effective way for splenic transplantation. The regeneration process of autotransplantated spleen may be divided into three stages: acute phase, remissive phase and renovate phase. During the stages, the blood vessels and nerve fibers complete their regeneration. The renascent blood vessels and nerve fibers come from greater omentum and extend into splenic autografts. The blood vessels regenerate more earlier than the nerve fibers. At early time after operation, the expression of VEGF and KDR in autotransplanted spleen increases quickly and instently prompts the vascular regeneration. When the regeneration process of blood vessels completes, the expression of VEGF and KDR in the splenic autotransplants decreases to normal.