TrkA AND TrkB EXPRESSION IN SPINAL MOTONEURONS FOLLOWING COMPLETE TRANSECTION OF RAT SPINAL CORD
Nie Duyu, Deng panyue, Cai Weijun, Zhang Jianyi, Wan wei *, Luo Xuegang(Department of Neurobiology, Xiangya Medical College, Central South University, Changsha, 410078)
The aim of this study was to seek for the expression pattern of neurotrophin receptors following the spinal cord transection in rats. The C 6 and L 5 spinal segments from the experimental animals were taken for detection of expression of TrkA and TrkB by immunohistochemistry, which was quantitated with HPIAS-1000 high-resolution color image cell-analysis system. We found that TrkA and TrkB receptors were up-regulated transiently in both C 6 and L 5 after complete spinal cord transection(SCT), but the peak expression of TrkA in C 6 occurred on day 14 postinjury whereas in L 5, it appeared on day 7. In contrast, the peaks of expression of TrkB in C 6 and L 5 were present on day 3 postinjury. Subsequently, the expression of both receptors decreased and returned to normal levels or below on day 28 postinjury. The data demonstrate the spatio-temporal patterns of the expression of TrkA and TrkB receptors following SCT. And the relationship between expression of TrkA and TrkB suggests that the expression of TrkA might be stimulated by the down-regulation of TrkB.