The Mechanisms Of NMDA Receptor NR2B Subunit In The Spinal Cord Of Inflammatory Rats

Part one: The effect of the inflammation on the plastic changes of the superficial lamiae of the lumbar spinal cord in ratsObjective To evaluate on the plastic changes of dorsal horn following the hind paw inflammation of the rats. Methods The 24 SD rats were divided randomly into three groups: the normal, saline and the model group. The normal groups rats received puncture in the right hind paw, but the saline groups received 100μl saline. the model groups received 2% carrageenan 100μl as well. After the injection we investigated the mechanical threshold of the pain and the thermal latency at 3 and 15 hours. After the record of the threshold, the rats were infused with 4% paraformaldehyde, the skin of the paw and the lumbar spinal cord were taken and dyed with Haematoxylin-Eosin to identify the hind paw inflammation and the structure of the lumbar spinal cord, Immunohistochemistry of NMDARsNR2B, nNOS, COX-2 were used, then to count the masculine neurons with the NMDARsNR2B, nNOS, COX-2 protein. Results The mechanical threshold and the thermal latency of the model groups were reduced compared with the other two groups (p<0.05). The paw skin infiltrated with the inflammatory cell. was damaged in the model group. The masculine cells with the NMDA NR2B, nNOS, COX-2 protein in the superficial lamiae of the lumbar spinal cord in the model group were more than the other two groups significantly. (p<0.05). Conclusion These findings suggest the inflammation in the hind paw could increase the expression of the protein NMDARs NR2B, nNOS, COX-2 in the superficial lamiae of the lumbar spinal cord and the inflammation in the hind paw could reduced the mechanical threshold and the thermal latency at that point.