NMDA受体在正常大鼠颈动脉体的表达

应用免疫组织化学方法观察了离子型谷氨酸受体——NMDA受体的NR1及NR2A亚单位在正常成年雄性SD和Wistar大鼠颈动脉体的表达,并对阳性产物的表达强度进行了灰度分析及统计学处理。结果表明:正常成年SD大鼠及Wistar大鼠的颈动脉体内均存在NMDA NR1免疫反应阳性细胞,从阳性细胞的形态和分布特点判断这些阳性细胞为主细胞,两种大鼠之间无明显差异(P>0.05);而两种大鼠的颈动脉体内几乎不存在NMDA NR2A免疫反应阳性细胞。本实验的结果提示:在正常成年大鼠颈动脉体的主细胞上有NMDA受体的分布,并且该受体的二聚体构成不同于经典受体,这可能与谷氨酸在颈动脉体发挥的特殊功能有关。

THE EXPRESSION OF NMDA RECEPTOR IN THE CAROTID BODY OF NORMAL RAT

The expression of NMDA receptor subunits NR1 and NR2A in the normal adult SD/ Wistar rats was studied by using immunohistochemistry combined with micro-image analysis system. The average grey values of the staining intensity in each group were compared by statistic methods. The results showed that some cells in the carotid body of either SD or Wistar rats were NR1 immunoreactive. The NR1-positive cells might be the type I cells judged from their morphological features and distribution pattern and there was no statistically significance in dying intensity between SD rats and Wistar rats ( P >0.05). No NR2A-immunoreactive cells in the carotid body in both species were detected. The above results indicate that NMDA receptors are expressed in the type I cells of normal adult rats' carotid body, but the composition of subunits may be quite different from the classical ones. This result may attribute to the special function of glutamate in the carotid body.