Grizzle W E, Johnson R N, Schramm L P, Gann D S
Am J Physiol. 1975 Apr;228(4):1039-45. doi: 10.1152/ajplegacy.1975.228.4.1039.
The right atrium has been shown to mediate release of ACTH in response to small hemorrhage. Therefore, we sought to identify hypothalamic neurons (cat, alpha-choloralose 35-45 mg/kg) wholse firing rates were modulated by stretch of the right atrial-vena caval junction. Stretch was produced by intermittent inflation of a balloon implanted between the pericardium and the right atrium. In some cases, carotid arteries were occluded bilaterally. Previous results indicate that electrical stimulation of the medial-dorsal hypothalamus (MDH) causes prompt changes in ACTH, but stimulation in the lateral hypothalamus does not cause changes. Of 64 cells recorded in the MDH, 41 responded to atrial stretch. However, only 2 of 18 cells outside this region responded. Six cells were studied with and without carotid occlusion. Their response was dimished or absent in the absence of carotid occlusion. The results suggest that integration of afferent signals from cardiovascular receptors occurs in the MDH and that the MDH may participate in neural mediation of ACTH in response to hemodynamic changes.
右心房已被证明可介导促肾上腺皮质激素（ACTH）在小出血反应中的释放。因此，我们试图识别下丘脑神经元（猫，α-氯醛糖35 - 45毫克/千克），其放电频率受右心房 - 腔静脉交界处的拉伸调节。拉伸是通过间歇性充胀植入心包和右心房之间的球囊产生的。在某些情况下，双侧颈总动脉被阻断。先前的结果表明，电刺激下丘脑背内侧核（MDH）会导致ACTH迅速变化，但刺激下丘脑外侧区则不会引起变化。在MDH记录的64个细胞中，41个对心房拉伸有反应。然而，该区域外的18个细胞中只有2个有反应。对6个细胞在有和没有颈总动脉阻断的情况下进行了研究。在没有颈总动脉阻断的情况下，它们的反应减弱或消失。结果表明，来自心血管感受器的传入信号整合发生在下丘脑背内侧核，并且下丘脑背内侧核可能参与ACTH对血流动力学变化反应的神经调节。
