高血压病人中枢α_2受体功能紊乱以及β受体阻断剂对它们的影响

THE DYSFUNCTION OF CENTRAL ALPHA 2 ADRENOCEPTORS IN HYPERTENSIVE PATIENTS AND THE INFLUENCES OF β-BLOCKING AGENTS ON IT

本文观察10例健康人与12例高血压病人以可乐定(clonidine)诱发生长激素释放的区别,还观察在β受体阻断剂普洛察尔(propranolol)作用1周后,10例高血压病人可乐定/生长激素(C/GH)的变化。研究证明:静注中枢神经α_2受体激动剂可乐定150μg后30,60min使正常人血清生长激素分别增加7.8与6.4倍,高血压病人仅分别增加2.3与1.7倍(P<0.01),高血压病人的中枢α_2受体对激动剂反应性下降。10例病人接受普洛萘尔治疗1周后,在已经出现明显的心率减慢,可乐定的降压作用已被抑制的同时,病人可乐定/生长激素反应低下的现象未能纠正。提示高血压病人中枢α_2受体功能障碍,可能是选择性的。

Clonidine, the central α_2 adrenoceptor agonist, inducedrelease of growth hormone was investigated in 10 normal subjects and 12hypertensive patients. The changes of growth hormone released by clonidinebefore and after β-blocking agent (propranolol) were studied as well. Growth hormone increased by 7 .8 and 6 .4 times, respectively after 30 and60 min of intravenouse clonidine 150μg normal subjects, compared to 2.3 and1 .7 times in hypertensive patients (P<0.01). The attenuated release ofgrowth hormone by clonidine in hypertensive patients could not be reversedhy propranolol (20mg tid 1wk) when the antagonism effect between pro-pranolol and clonidine was occurred. It is thus suggested that there is aselective impairment of the α_2 adrenergic mechanism controlling growthhormone release in hypertensive patients.