Yuan C S, Barber W D
Department of Anatomy, University of Arizona, Tucson 85724.
Brain Res Bull. 1990 Nov;25(5):685-90. doi: 10.1016/0361-9230(90)90043-y.
The response of neurons in the ventral and dorsal tegmental nuclei during electrical stimulation of the gastric vagal fibers which serve the proximal stomach and the left greater splanchnic fibers were evaluated in chloralose-anesthetized cats. The mean latency of 181 gastric vagally evoked unitary responses recorded in the tegmental nuclei was 352.2 ms, whereas the latency of the left greater splanchnic-evoked tegmental response was significantly less (63.2 ms). The unitary responses to the gastric vagal and greater splanchnic fibers stimulation were bilaterally distributed in the ventral and dorsal tegmental nuclei. Convergence of the gastric vagal input from the proximal stomach and the left greater splanchnic input was observed in 151 units (83 percent). Stimulation of the greater splanchnic nerve usually resulted in a short latency excitation followed by an inhibitory effect on gastric vagally evoked responses. The results suggested that some convergent splanchnic inhibition of gastric vagally evoked responses was mediated via an interneuron. Projections from the nucleus tractus solitarius and the parabrachial nucleus to the tegmental nuclei were also identified electrophysiologically by direct microstimulation of the two former areas. The significant number of gastric vagal and splanchnic evoked unitary responses recorded in the ventral and dorsal tegmental nuclei suggested that they may serve as an important pontine site for processing of visceral information between the nucleus tractus solitarius and forebrain sites.
在水合氯醛麻醉的猫身上，评估了支配胃近端的胃迷走神经纤维和左内脏大神经纤维电刺激期间腹侧和背侧被盖核中神经元的反应。在被盖核中记录到的181个胃迷走神经诱发的单位反应的平均潜伏期为352.2毫秒，而左内脏大神经诱发的被盖反应的潜伏期明显更短（63.2毫秒）。对胃迷走神经和内脏大神经纤维刺激的单位反应双侧分布于腹侧和背侧被盖核。在151个单位（83%）中观察到来自胃近端的胃迷走神经输入和左内脏大神经输入的汇聚。刺激内脏大神经通常会导致短潜伏期兴奋，随后对胃迷走神经诱发的反应产生抑制作用。结果表明，一些对胃迷走神经诱发反应的内脏大神经汇聚性抑制是通过中间神经元介导的。通过直接微刺激孤束核和臂旁核这两个区域，还从电生理学上确定了它们向被盖核的投射。在腹侧和背侧被盖核中记录到的大量胃迷走神经和内脏大神经诱发的单位反应表明，它们可能是孤束核和前脑部位之间处理内脏信息的重要脑桥部位。
