Tebbe J J, Dietze T, Grote C, Mönnikes H
Department of Anatomy and Cell Biology, Philipps-Universität zu Marburg, Marburg, Germany.
Brain Res. 2001 Sep 14;913(1):10-7. doi: 10.1016/s0006-8993(01)02746-9.
It is well established that autonomic control of gastrointestinal function is modulated by central autonomic neurotransmission. In this context it has been shown that gastrointestinal motility and secretion can be modulated by exogenous neuropeptides microinjected into the paraventricular nucleus of the hypothalamus (PVN). Furthermore, there is considerable evidence suggesting that neurons projecting from the arcuate nucleus (Arc) to the PVN may be the source of endogenous neuropeptide release in the PVN. This poses the question whether stimulation of neurons in the arcuate nucleus, e.g. by an excitatory amino acid, alters gastrointestinal function. In the present study, we investigated the effect of an excitatory amino acid, kainate, microinjected into the arcuate nucleus on gastric acid secretion in urethane-anesthetized rats. Kainate (140 pmol/rat) bilaterally microinjected into the Arc induced an significant inhibition of pentagastrin (PG) stimulated (16 mg/kg per h) gastric acid secretion throughout an observation period of 120 min after microinjection. Microinjection of kainate into hypothalamic areas outside the arcuate nucleus did not modify gastric secretion. Bilateral cervical vagotomy blocked the effect of kainate injected into the Arc on PG-stimulated gastric acid secretion. These data show that gastric secretory function can be modulated by stimulation of neuronal activity in the Arc via efferent vagal pathways. The results suggest that the arcuate nucleus is a forebrain area involved in the CNS regulation of gastrointestinal function.
自主神经对胃肠功能的控制是由中枢自主神经传递调节的，这一点已得到充分证实。在这种情况下，研究表明，向下丘脑室旁核（PVN）微量注射外源性神经肽可调节胃肠蠕动和分泌。此外，有大量证据表明，从弓状核（Arc）投射到PVN的神经元可能是PVN内源性神经肽释放的来源。这就提出了一个问题，即刺激弓状核中的神经元，例如通过兴奋性氨基酸，是否会改变胃肠功能。在本研究中，我们研究了向弓状核微量注射兴奋性氨基酸海藻酸对氨基甲酸乙酯麻醉大鼠胃酸分泌的影响。向双侧弓状核微量注射海藻酸（140 pmol/只大鼠），在注射后120分钟的观察期内，对五肽胃泌素（PG）刺激（16 mg/kg每小时）的胃酸分泌产生了显著抑制作用。向弓状核以外的下丘脑区域微量注射海藻酸并未改变胃液分泌。双侧颈迷走神经切断术阻断了向弓状核注射海藻酸对PG刺激的胃酸分泌的影响。这些数据表明，胃酸分泌功能可通过传出迷走神经途径刺激弓状核中的神经元活动来调节。结果表明，弓状核是参与中枢神经系统对胃肠功能调节的前脑区域。
