杏仁中央核在躯体传入冲动抑制中枢性升压反应中的作用

THE ROLE OF AMYGDALA IN THE INHIBITORY EFFECT OF SOMATIC AFFERENT INPUTS ON THE CENTRAL PRESSOR RESPONSE

目的:阐明电刺激腓深神经(DPN)对下丘脑室旁核(PVN)兴奋后的心血管反应的调节作用及杏仁中央核(CeA)在此作用中的地位。方法:电刺激SD大鼠中枢核团PVN,或用核团(CeA)内微量注射法注射L-谷氨酸钠(L-Glu)或红藻氨酸(KA)。同时记录大鼠股动脉血压、平均动脉压(MAP)、心电图及心率(HR)曲线。结果:电刺激一侧PVN后,MAP升高,HR变化不一,以下降为主。电刺激腓深神经对PVN兴奋诱发的升压反应有抑制作用。在同侧CeA微量注射0.02mol/L的KA100nl,10min后刺激PVN,血压升高(13.8±3.2)mmHg,较注射KA前削弱了(6.6±1.6)mmHg(P<0.05),DPN对刺激PVN的升压反应的抑制百分比也从51.5%降为32.0%。结论:杏仁中央核部分介导了PVN兴奋后引起的升压反应。DPN传入冲动对PVN中枢性升压反应有抑制作用,其机制可能与杏仁中央核有关。

Aim：To investigate the inhibitory effect of the deep peroneal nerve（DPN）on the cardiovascular responses induced by excitation of the paraventricular nucleus of hypothalamus（PVN）and the role of central nucleus of amygdala（CeA）in this effect.Methods：CeA was injected by L-glutamate or Kainic acid（KA）.The femoral arterial pressure,mean arterial pressure（MAP）,electrocardiogram（ECG）and heart rate（HR）of SD rats were recorded while PVN or DPN was electrically stimulated.Results：It showed that MAP increased when PVN was activated by electrical stimulation.Stimulating contralateral DPN inhibited this pressor response.Ten minutes after microinjection of KA（0.02 mol/L,100 nl）into ipsilateral CeA,MAP increased for（13.8±3.2）mmHg when PVN was stimulated.Microinjection of KA into CeA could not only reduce the pressor response elicited by stimulation of PVN for（6.6±1.6）mmHg（P〈0.05）,but also the inhibitory effect of DPN from 51.5% to 32.0%.Conclusion：The results suggest that central nucleus of amygdala partly mediate the central pressor response induced by stimulation of PVN.The neurons in central nucleus of amygdala are involved in the inhibitory effect of DPN on the above pressor response.