Observations on the blood and perineurial permeability barriers of surviving nerve allografts in immunodeficient and immunosuppressed rats.

摘要: The authors investigate whether there are any permeability changes in the endoneurial blood-nerve barrier and perineurium-nerve of surviving nerve allografts. In a normal nerve, regulates passage substances from blood vessels into endoneurium, whereas protects endoneurium agents that escape permeable epineurial accumulate around nerve. Nerves ACI rats were transplanted immunologically deficient nude or Fischer immunosuppressed with cyclosporin A. None allografts was rejected. at 2 6 weeks postoperatively to intravenously injected horseradish peroxidase, which spread tissue. Electron microscopy revealed peroxidase escaped through intercellular junctions between endothelial cells. At 24 weeks, had recovered vessels, like those nerves, impermeable peroxidase. remained all times. Axons grouped numerous minifascicles anastomosis zones weeks. Each fascicle surrounded by an perineurium. These results demonstrate regenerated axons long-term protected barriers. It is concluded barriers not permanently altered foreign environment (grafts rats) even when immunosuppression A required prevent allograft rejection rats).