短暂性前脑缺血后大鼠海马各区NMDA受体亚单位1 mRNA的表达变化

目的观察短暂性前脑缺血后大鼠海马各区N-甲基-D-天门冬氨酸受体(NR)1 mRNA的表达变化。方法采用大鼠前脑缺血15min再灌注0．5h～7d动物模型和原位杂交、图像分析等技术。结果缺血后，海马CA1区NR1 mRNA的表达呈明显上升趋势，至24h达高峰；然后表达开始回落，至缺血后7d降至低谷。在CA3区，NR1 mRNA的表达变化与CA1区类似，但变化幅度明显减小。在齿状回，缺血后0．5h～72h，NR1 mRNA的表达未见显著性变化；缺血后7d，表达亦显著降低。结论短暂性前脑缺血后，大鼠海马各区RN1mRNA的表达变化不同，这种不同可能与海马的选择性易损现象和迟发性细胞死亡有关。

ALTERATIONS OF NMDA RECEPTOR SUBUNIT 1 mRNA EXPRESSION IN HIPPOCAMPUS OF RAT FOLLOWING TRANSIENT FOREBRAIN ISCHEMIA

Objective To observe the expression of NMDA receptor subunit 1 mRNA in hippocampus of rat following transient forebrain ischemia. Methods Fifteen minutes forebrain ischemia and 05h-7d reperfusions (IR) model of rats were created by four-vessel occlusion.The expression of NR1 mRNA was examined by in situ hybridization histochemistry and image analysis system. Results After IR, the expression of NR1 mRNA raised up obviously in the CA1 region and reached to the highest at IR 24h. Then its expression came back and dropped to the lowest on the IR 7d. The pattern of NR1 mRNA expression in the CA3 region was similar to that in the CA1 region, but the range of its change was less abrupt than that in the CA1. The expression of NR1 mRNA in the dentate gyrus had no significant change until IR/72h,and dropped to the lowest on the IR7d.Conclusion The expression of NR1 mRNA in hippocampus of rat showed different time and region dependent patterns after transient forebrain ischemia.These patterns suggest that the alterations of NR1 mRNA expression may contribute to selective vulnerability and delayed cell death of hippocampus.