An Experimential Study On Expression Changes Of MCP-1 And BDNF After Acute Spinal Cord Injury In Rats

Objective: To research the shape changes of neural cells, expression of MCP-1 and its effect on macrophages, and expression of BDNF after acute spinal cord injury in rats;To explore the mechanism of spinal cord continual injury and the relationship between it and the restoration of the neural cells .Method: Wistar adult rats(n=60)weighting 280±10g. 60 rats were divided randomly into 6 groups, injury groups and laminectomy groups.Each group was 10 rats. The laminectomy rats were used to control group. Injury groups were strike by a steel stick at the root of the spinal cord of T8-T9. Injury groups were filled by 4% formaldehyde or 3% glutaraldehyde at 3,6,12,24,72 hours..Then took out the spinal cord.The spinal cords of rats which were filled by 3 % glutaraldehyde were observed by electron microscope and the others which were filled by 4% formaldehyde were observed by HE dyes about neural cells apoptosis.The last which were filled by 4% formaldehyde were observed by immunohistochemistry about the expression of MCP-1, BDNF and about infiltration of macrophages.Results:1. After rat acute spinal cord injury, by HE dyes and electron microscope, the apoptosis of neural cells began from 6 hour to 24 hour.The typical shape of neural cells apoptosis appeared at 72 hours.2. Three hours after the acute spinal cord injury, the density mean of the positive cells of MCP- 1 , BDNF and macrophages were significantly more high than laminectomy groups in damage area (P<0.05). The density mean of the positive cells of MCP- 1 was the most high at 24 hours(P<0.05). The density mean ofmacrophages and the density mean of the positive cells of BDNF was the most high at 72 hours(P<0.05). Conclusions:1. The apoptosis of neural cells, MCP-1 and macrophages all take park in the spinal cord continual damage.2. The macrophages can be tended towards by MCP-1.And the peak of the density mean of macrophages was delay the density mean of the positive cells of MCP-1.3. After the acute spinal cord injury,BDNF took park in the restoration of the neural cells.