氯沙坦通过室旁核抑制慢性心衰大鼠肾交感神经兴奋性

目的：研究慢性心衰时室旁核微量注射氯沙坦对心率、血压和肾交感神经的作用，揭示心衰下丘脑室旁核对肾交感神经活性的调节机制。方法：用SD大鼠制作心衰模型，超声心动图检测心功能变化。脑立体定位仪对大鼠室旁核定位，微量注射氯沙坦（50nL），观察心率、血压和肾交感神经活性的变化。结果：超声心动图显示手术组较假手术组左室内径增加（P〈0．01），射血分数降低（P〈0．01），左室内径缩短率降低（P〈0．05）。注射氯沙坦后，手术组和假手术组的肾交感神经兴奋性降低，手术组较假手术组降低更为明显。结论：心衰时室旁核内注射氯沙坦可降低肾交感神经兴奋性。

Losartan inhibits renal sympathetic nerve activity in Paraventricular nucleus in chronic heart failure rat

AIM:Left coronary artery ligation(LAD)was used to induce heart failure.Losartan was microinjected into paraventricular nucleus(PVN),heart rate(HR),blood pressure(BP)and renal sympathetic nerve activity(RSNA)were measured.The mechanism of PVN in chronic heart failure was investigated.METHODS:Sprague-Dawley male rats were selected for LAD ligation for heart failure models,the variation of cardiac function was detected by echocardiography.Losartan was microinjected into PVN,the responses of HR,BP and RSNA were analyzed.RESULTS:Compared with sham group,the level of LV was increased(P＜0.01),the levels of EF and FS were decreased in operation group(P＜0.01,P＜0.05).The level of RSNA was decreased greater in operation group than that in sham group(P＜0.05). CONCLUSION: Losartan microinjection into PVN can decrease the level of RSNA in chronic heart failure.