Effect of Intrathecal Transplantation of Adrenal Medullary Tissue on the Sciatic eNe Regeneration Following Chronic Constriction Injury in the ~at

Transplants into the spinal subarachnoid space can alleviateneuropathic pain behaviors. the aim of the present study was to testthe possibility that histological changes of the sciatic nerve in aneuropathic model as well as sensory dysfunction are repaired byadrenal medullary transplantation.material and methods: left sciatic nerve was ligated in threegroups of rats by 4 loose ligatures (eel). after one week of nerveconstriction, rats of first group were implanted with adrenal medullarytissue (eel + adrenal medulla) and rats of the second group withstriated muscle at the level of l1-l2 (eel + muscle). the third groupreceived only left ligature (eel) and in the fourth group the sciaticnerve was exposed and then muscle and skin sutured (sham).behavioral assessment was evaluated before surgery and 2, 4, 7, 10,14, 21, 28, 42, and 56 days after the onset of experiment. accordingto behavioral results, 4 rats in each group were anesthetized andthen the distal part of sciatic nerve were isolated and prepared forhistological quantitative investigation of nerve regeneration.results: the results showed that eel was accompanied withhyperalgesia and morphological changes in the distal part of sciaticnerve. in animals with adrenal medullary transplantation, not onlyhyperalgesia was markedly reduced or even eliminated, but also thenumber of myelinated fibers in the distal segment of nerve increasedto nearly normal.conclusions: our findings showed that the implantation of adrenalmedullary tissue might have caused regeneration of ligated nervesas well as alleviation of pain behavior.