中枢5-HT_(1A)受体激动剂可改善自发性高血压大鼠的红细胞变形性

STIMULATING CENTRAL 5-HT_(1A) RECEPTOR COULD IMPROVE THE RBC DEFORMABILITY OF SPONTANEOUSLY HYPERTENSIVE RAT

给戊巴比妥钠麻醉的正常大鼠侧脑室注射(i.c.v.)5-BT_(1A)R高选择性激动剂8-OH-DPAT,可产生剂量依赖的降压效应;而给自发性高血压大鼠(SHR)i.c.v.8-OH-DPAT(20μg/10μl)却观察到在血压升高的同时,RBC变形性有明显改善。另外直接作用于RBC膜的因素不是5-HT或8-OH-DPAT。本工作首次证明,中枢神经系统(CNS)不仅对血液动力学状态,而且对血液流变学状态也具有调节作用。

In order to investigate whether the CNS could regulate the blood rheology, we first meas-ured RBC deformability of nomotensive rats and spontaneously hypertensive rats(SHR), respectivelywith ektacytometry and found that the RBC deformability of SHR was improved to a markedly greaterdegree than that of nomotensive rats. I. c.v. injection of 8-OH-DPAT(20μg),one of the 5-HT_(1A) recep-tor agonists that had hypotensive effect on nomotensive rats,was givea to SHR, the mABP and HR didnot decrease but increase aud at the same time deformability of RBC membrane improved, whereasadministrated 5-HT(100μg)or 8-OH-DPAT(20μg)directly to the blood, no significant change in RBCdeformnbility was observed. So we think that CNS could not only regulate the state of blood dynami-cs, but also the state of blood rheology. The ceatral 5-HA_(1A) receptor, 8-OH-DPAT could improve theRBC deformability, but the last effective factor might not be 5-Hr or 8-OH-DPAT. There must besome other substances to take part in, such as EDCF, EDRF, PDGF, ET, CGRP, etc. The improveme-nt of RBC deformability in hypertensive state might be a kind of compensatory effect in pathologicalstate.