Dorsal motor nucleus of the vagus: a site for evoking simultaneous changes in crural diaphragm activity, lower esophageal sphincter pressure, and fundus tone.
Dorsal motor nucleus of the vagus: a site for evoking simultaneous changes in crural diaphragm activity, lower esophageal sphincter pressure, and fundus tone.
复制标题
DOI：
10.1152/ajpregu.00391.2007
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
Mark Niedringhaus;P. Jackson;S. Evans;J. Verbalis;R. Gillis;N. Sahibzada
中科院分区：
文献类型：
--
作者：
Mark Niedringhaus;P. Jackson;S. Evans;J. Verbalis;R. Gillis;N. Sahibzada
食管胃交界处的括约肌机制包括食管下段的平滑肌和脚横肌（CD）的骨骼肌。平滑肌受迷走神经背侧运动核（DMV）的控制，而中枢神经系统（CNS）对CD的控制尚不清楚。本研究的主要目的是确定控制CD的中枢神经系统部位，以及当该部位被激活时，是否会同时发生食管下括约肌（LES）压力和CD活性的变化。实验以麻醉的雄性雪貂为实验对象，监测其LES压、CD活性和眼底张力。为了激活DMV神经元，将l -谷氨酸单侧微注射到DMV的三个区域：中间、吻侧和尾侧。中间DMV刺激降低CD活性（-4.8 +/- 0.1脉冲/分钟和-0.3 +/- 0.01 mV）和LES压力（-13.2 +/- 2.0 mmHg, n = 9）。刺激这一大脑部位也会增加眼底张力。刺激吻侧DMV引起所有三个目标器官的活性增加（n = 5）。刺激尾侧DMV对CD没有影响，但确实降低了LES压力和眼底张力（n = 5）。同侧迷走神经切开术可以预防LES压力、眼底张力的所有变化和dmv引起的CD活动的一些变化（即脉冲/分钟）。我们的数据表明，食管胃括约肌活动和眼底张力的同时变化发生在DMV的吻侧和中间区域，这些变化主要是由传出迷走神经介导的。
The sphincter mechanism at the esophagogastric junction includes smooth muscle of the lower esophagus and skeletal muscle of the crural diaphragm (CD). Smooth muscle is known to be under the control of the dorsal motor nucleus of the vagus (DMV), while central nervous system (CNS) control of the CD is unknown. The main purposes of our study were to determine the CNS site that controls the CD and whether simultaneous changes in lower esophageal sphincter (LES) pressure and CD activity occur when this site is activated. Experiments were performed on anesthetized male ferrets whose LES pressure, CD activity, and fundus tone were monitored. To activate DMV neurons, L-glutamate was microinjected unilaterally into the DMV at three areas: intermediate, rostral, and caudal. Stimulation of the intermediate DMV decreased CD activity (-4.8 +/- 0.1 bursts/min and -0.3 +/- 0.01 mV) and LES pressure (-13.2 +/- 2.0 mmHg; n = 9). Stimulation of this brain site also produced an increase in fundus tone. Stimulation of the rostral DMV elicited increases in the activity of all three target organs (n = 5). Stimulation of the caudal DMV had no effect on the CD but did decrease both LES pressure and fundus tone (n = 5). All changes in LES pressure, fundus tone, and some DMV-induced changes in CD activity (i.e., bursts/min) were prevented by ipsilateral vagotomy. Our data indicate that simultaneous changes in activity of esophagogastric sphincters and fundus tone occur from rostral and intermediate areas of the DMV and that these changes are largely mediated by efferent vagus nerves.