自发性高血压大鼠脑动脉心钠素受体分布的计量学研究

用软脑膜铺片技术，兔疫组织化学方法及全自动图像分析仪对１７周龄自发性高血压大鼠脑血管床心钠素受体分布密度进行研究、结果表明，自发性高血压大鼠脑小动脉及细动脉壁上心钠素受体分布密度明显低于正常血压大鼠，Ｐ＜０．０１。此外，在细小动脉分叉部位心钠素受体分布密度增加，而自发性高血压大鼠中其分叉部位的受体密度明显低于正常血压大鼠。从实验结果显示，我们试用的软脑膜铺片技术显然弥补了组织切片中从血管横断面观察心钠素受体分布的局限性，清楚地展现了整个血管床心钠素受体分布特征。根据实验结果提示这些阻力性动脉心钠素受体密度减少与细小动脉舒血管反应减弱，外周阻力增加，血压升高有着明显的关系；尤其是对调节外周循环血量和外周阻力充当闸门作用的细小动脉分叉部位，心钠素受体密度降低这一特征在高血压发生机制中可能起着重要作用。

METROLOGICAL STUDY OF ATRIAL NATRIURETIC PEPTIDE RECEPTOR IN CEREBRAL ARTERIES OF SPONTANEOUSlY HYPERTENSIVE RATS

Method of sheeting from pla mater, immunohistochemical techniques and image analyser were used to study the density of atrial natriuretic peptide (ANP) receptor in cerebral arteries of spontaneously hypertensive rats (SHR) at 17 weeks of age. The results show that volumetric and integral luminolls density of binding sites for ANP in cerebral small arteries and arterioles of SHR was significantly lower than that of normal ones (P<0. 01 ). Moreover,the density of ANP receptor was increased in the fork regions between small arteries and arterioles as compared with that in the distal regions of arterioles but in SHR it was markedly decreased in comparison with that observed in normal one. The above findings demonstrated that the method of sheeting from pla mater exhibited clearly the characteristics of ANP receptor distribution throughout vascular network and compensated for the limitations when ANP receptors were observed at transverse section of arteries. Our results suggest that the decrease in density of ANP receptors in resistant arteries of SHR has an obvious relation to the lower sensitivity of diastolic vessel response to ANP, increase of peripheral circulatory resistance and raise of blood pressure. In particular, the characteristic decrease in ANP receptors density in fork regions of arterioles that act as sluice gate to adjust peripheral circulatory blood volume and resistance may play an important role in the development mechanism of hypertension in SHR.The project supported by National Natural Science Foundntion of China (NSFC)