Experimentation On Transplantation Of Xenogenic Small Vessels

Purpose: To investigate the patency rate of the transplanted xenogenic vessels which have had endomembrane been removed and the ultrastructure of the superficial endomembrane of the xenogenic vessels. Method: Use xenogenic vessels that had been dealt by removal of the endomembrane, frozen and drying to anastomose to the femoral artery and vein of dogs, then investigate the patency rate of the xenogenic vessels by using Doppler auscultator in one , two, four, eight, twelve, sixteen and twenty weeks after the transplantation, meanwhile, collect specimens to do observation by scanning electronic microscope. Use xenogenic vessels which have been dealt by removal of the endomembrane and frozen and drying to ligate to bilateral common carotid artery of the rabbits, then investigate the patency rate of the xenogenic vessels after transplantation for one, two and three months.Results:1. All of the fourteen dogs are survival after implantation of the xenogenic vessels to their femoral artery, without any infection of the wound, and have excellent pulsation of the distal artery in the transplantation sides. In dissection, the xenogenic vessels are encapsulated by ambient tissues. When longitudinal split, the xenogenic vessels have smooth and complete tunica intima without formation of thrombus and obvious thickening and stenosis of the vessel walls, the anastomotic stomas are smooth. The ultrastructure changes of the xenogenic vessels implanting to the femoral artery in different stages are as follows:1.1 one week after operation, wraps of smooth cellulose overjetting on the xenogenic vessels with a sprinkle of red blood cells and white blood cells on the surfaces are detected by scanning electronic microscope.1.2 two weeks after operation, fusiform cells appeared in the anastomotic stomas of the xenogenic vessels by scanning electronic microscope while other parts of the vessels are still covered by wraps of cellulose though the morphous of the endothelial cells are longer and thinner compared to those of jacent autogenic vessels.1.3 four weeks after operation, more fusiform cells or elliptic cells on the xenogenic vessels are detected by scanning electronic microscope though the alignments of the cells are still irregular.1.4 eight weeks after operation, abundant fusiform cells or elliptic cells on the xenogenic vessels could be detected by scanning electronic microscope, though there still have gaps exist among the cells.1.5 twelve weeks after operation, the surfaces of the xenogenic vessels are almost overlaid by fusiform cells and elliptic cells with regular alignments of the cells and formation of the endomembrane; the surfaces of the xenogenic vessels are completely overlaid by fusiform cells with"road rocks"appearance and cohered by several blood cells on detecting by scanning electronic microscope.1.6 sixteen weeks after operation, the endomembrane are smooth on observation by scanning electronic microscope.1.7 twenty weeks after operation, much more smooth than that of in sixteen weeks.2. Transplant of the xenogenic vessels without endothelial cells to the femoral veins of dogs.All of the implanted vessels are occluded within one week without any frequency spectrum of the blood flow.3. Transplant of the xenogenic vessels without endothelial cells to the common carotid arteries of rabbits.3.1 one month after operation, all the xenogenic vessels are to be unobstructed.3.2 two months after operation, the patency rate of the xenogenic vessels is 94.4%.3.3 three months after operation, the patency rate of the xenogenic vessels is 94.1%.Conclusion: The xenogenic vessels without endothelial cells have satisfactory histocompatibility and compliance, xenogenic arteries could remain easy and smooth in short period: endothelial cells could cover the surface of the xenogenic vessels without obvious hyperplasia of the endomembrane.