Analysis of effect of autologou bone marrow transplantation in neurogenic pain model

2006 Fiscal Year Final Research Report Summary

• Project/Area Number: 17500360
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Rehabilitation science/Welfare engineering
• Research Institution: Hiroshima University
• Principal Investigator: ITO Yoshihiro Hiroshima University, Hospital, Physical Therapist (60397958)
• Co-Investigator(Kenkyū-buntansha): KIMURA Hiroaki , Assistant Professor (60363074) ; TSUTSUMI Eriko HIROSHIMA UNIVERSITY, Graduate School of Health Science, Research Associate (40304422) ; SARADA Kazuhiro , Physical Therapist (20423353)
• Project Period (FY): 2005 – 2006
• Keywords: rehabilitation / transplantation / tissue engineering / neuroscience

Research Abstract

Complex regional pain syndrome develops after noxious events such as sprains, various injuries, fracture, nerve lesions or surgery. It is characterized by severe pain, allodynia, edema, discoloration and autonomic disorders. Details of the mechanism remain unclear. Bone marrow transplantation promotes angiogenesis in the lower leg with arteriosclerosis obliterans and reduces severe pain for a few days. We therefore analyzed the effect of autologous bone marrow transplantation in the rat model of neurogenic pain that is usually used to study complex regional pain syndrome.
We initially applied an immunohistochemical stain to detect calcitonin gene-related peptide and substance-P in the spinal cord and muscle of affected paws and then compared pain thresholds between Sprague-Dawley and Wistar Lewis rats. We improved the coated wire mesh floor of the cages and constructed a pain behavior chart that originally comprised 12 items. Thereafter, bone marrow from another Lewis rat was transplanted into a 7-week-old model of chronic contraction injury (n=7), and cultured mesenchymal stem cells transplanted from Lewis rats into another group (n=7). The control group comprised chronic contraction injured Lewis rats (n=7). The results were not statistically related among the three groups, changes in pain behavior were transient. And immunohistochemical changes were absent. In following year, we transplanted bone marrow into the subarachnoid space of the 7-week-old model of chronic contraction injury and found an increased pain threshold on the first post-operative day. Statistical significance was difficult to ascertain because the number of rats was too small.
We therefore plan to explore these transplantation methods in a larger number of rats.