芦沙坦的降压效应和内、外侧缰核神经元单位放电的关系

目的和方法 :观察腹腔注射 (i.p) 2mg kg和 10mg kg芦沙坦 (losartan)对大鼠股动脉血压 (aterialbloodpressure ,AP)和心率 (heartrate,HR)的影响以及与缰核 (Hb)神经元活动的关系。用玻璃微电极记录内侧缰核 (MHb)、外侧缰核(LHb)神经元单位放电活动 ,观察 10mg kg芦沙坦对其放电频率的影响。结果 :2mg kg芦沙坦对大鼠AP和HR无明显影响 ;(10mg kg芦沙坦可显著降低大鼠动脉血压 ,但对心率无明显影响。 10mg kg芦沙坦可使LHb内 6 6 6 6 % 12 18)神经元单位放电频率增加 ,使MHb内 6 1 90 % (13 2 1)神经元单位放电频率减少。结论 :10mg kg芦沙坦可明显地降低大鼠AP ,但 2mg kg芦沙坦对AP无明显影响 ;10mg kg芦沙坦可兴奋LHb和抑制MHb,产生降压效应

Effect of losartan on arterial blood pressure and unit discharging of neurons in LHb and MHb of rat

Aim and methods:To investigate the effect of 2 mg/kg and 10 mg/kg losartan intraperitoneally(i.p) on arterial blood pressure(AP) and heart rate(HR) in rat and the involvement in the activity of habenulat neurons. Glass micropipette was used to record any changes of unit dischargings of neurons in LHb and MHb before and after losartan was intraperitoneally injected. Results: AP and HR were not significantly changed by 2 mg/kg losartan(i.p). However,AP was apparently decreased by 10mg/kg losartan(i.p),but HR was unchanged. After 10 mg/kg losartan(i.p),66.66%(12/18) unit dischargings of neurons in LHb were increased in frequency,and 61.90%(13/21) in MHb were decreased.Conclusion: AP of rat was significantly decrased by 10mg/kg losartan(i.p). Depressor effect of losartan(i.p) was involved in the excition of neurons in LHb and the inhibition in MHb.