Cardiovascular effects of posterior hypothalamic stimulation in baroreflex-denervated rats.
Cardiovascular effects of posterior hypothalamic stimulation in baroreflex-denervated rats.
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DOI：
10.1152/ajpheart.1990.259.3.h720
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发表时间：
1990-09
期刊：
影响因子：
--
通讯作者：
K. Barron;C. Heesch
中科院分区：
文献类型：
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作者：
K. Barron;C. Heesch
本研究的总体目的是检查窦主动脉压力感受器去神经（SAD）对电刺激下丘脑后部的心血管和交感神经流出反应的影响。在实验前7-10天经历SAD的麻醉大鼠中，电刺激下丘脑后部引起平均动脉压、髂血管阻力、肠系膜血管阻力和腰交感神经活动比假手术压力感受器完整动物更大的增加。同样，与压力感受器完整组相比，压力感受器去神经组静脉注射去甲肾上腺素的升压作用也增强。当后下丘脑和静脉注射去甲肾上腺素升压刺激，产生等效的升压反应，在假手术压力感受器完整的动物，在压力感受器去神经的动物进行比较，中央下丘脑刺激的升压效果增强到更大的程度比去甲肾上腺素升压效果。这些数据提供的证据表明，动脉压力感受器反射发挥更大的缓冲升压刺激发起的中枢神经系统相比，由于外周血管血管收缩剂的升压反应。
The overall purpose of this study was to examine the effect of sinoaortic baroreceptor denervation (SAD) on the cardiovascular and sympathetic outflow responses to electrical stimulation of the posterior hypothalamus. In anesthetized rats that had undergone SAD 7-10 days before experimentation, electrical stimulation of the posterior hypothalamus elicited greater increases in mean arterial pressure, iliac vascular resistance, mesenteric vascular resistance, and lumbar sympathetic nerve activity than in sham-operated baroreceptor-intact animals. Similarly, the pressor effects of intravenous norepinephrine were also augmented in the baroreceptor-denervated group compared with the baroreceptor-intact group. When posterior hypothalamic and intravenous norepinephrine pressor stimuli, which produced equivalent pressor responses in sham-operated baroreceptor-intact animals, were compared in baroreceptor-denervated animals, the pressor effects of the central hypothalamic stimulus were enhanced to a greater degree than the norepinephrine pressor effects. These data provide evidence that arterial baroreceptor reflexes exert greater buffering of pressor stimuli initiated from the central nervous system compared with pressor responses due to peripheral vascular vasoconstrictor agents.