Ueta Y, Kannan H, Yamashita H
Department of Physiology, University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan.
Exp Brain Res. 1991;84(3):487-94. doi: 10.1007/BF00230960.
Extracellular recordings were made from vasopressin (AVP) and oxytocin (OXT)-secreting cells in the paraventricular nucleus (PVN) of the hypothalamus in rats anesthetized with urethane-chloralose to determine the effects of electrical stimulation of vagal gastric nerves and gastric distension on their activity. Electrical stimulation of gastric branches of the vagus nerves inhibited 5 and excited 10 of 32 phasically firing neurosecretory cells. Approximately one third of the phasically firing neurosecretory cells (9 out of 29 cells) were transiently inhibited by gastric distension; an effect which was completely abolished by bilateral cervical vagotomy. In contrast, gastric nerve stimulation excited 45 of 72 non-phasically firing paraventricular cells. Thirteen of 77 non-phasically firing cells tested were excited by gastric distension. We conclude that there are some sensory afferent inputs originating from gastric receptors and transmitted by gastric vagal afferents which inhibit the activity of AVP-secreting neurons in the PVN although other inputs excite the cells. Similar inputs also excite some of the putative OXT-secreting neurons in the PVN.
采用细胞外记录法，在氨基甲酸乙酯-氯醛糖麻醉的大鼠下丘脑室旁核（PVN）中，对分泌血管加压素（AVP）和催产素（OXT）的细胞进行记录，以确定电刺激迷走神经胃支和胃扩张对其活动的影响。电刺激迷走神经的胃支可抑制32个呈位相性放电的神经分泌细胞中的5个，并兴奋其中10个。约三分之一呈位相性放电的神经分泌细胞（29个细胞中的9个）受到胃扩张的短暂抑制；双侧颈迷走神经切断术可完全消除这种效应。相比之下，电刺激胃神经可兴奋72个非位相性放电的室旁核细胞中的45个。在77个接受测试的非位相性放电细胞中，有13个受到胃扩张的兴奋。我们得出结论，存在一些源自胃感受器并通过迷走神经胃传入纤维传导的感觉传入输入，这些输入抑制PVN中分泌AVP的神经元活动，尽管其他输入会兴奋这些细胞。类似的输入也会兴奋PVN中一些假定的分泌OXT的神经元。
