Sang Q, Young H M
Department of Anatomy and Cell Biology, University of Melbourne, Parkville, VIC, Australia.
Anat Rec. 1998 Jun;251(2):185-99. doi: 10.1002/(SICI)1097-0185(199806)251:2<185::AID-AR6>3.0.CO;2-Y.
The recent availability of antisera to the vesicular acetylcholine transporter (VAChT) and choline acetyltransferase (ChAT) that demonstrate peripheral cholinergic neurons has made possible the anatomical identification of cholinergic neurons in the enteric nervous system. In this study, we localised cholinergic neurons in the mouse small and large intestine and identified which substances are found colocalised in the cholinergic neurons.
Immunohistochemical single and double staining techniques were used on whole mount preparations and frozen sections to examine the localisation and chemical coding of cholinergic neurons in the small and large intestine of the mouse. Cholinergic neurons were identified using antisera to ChAT or VAChT.
In both the small and large intestine, numerous ChAT-immunoreactive nerve cell bodies were present in the myenteric and submucous ganglia, and ChAT- and VAChT-immunoreactive nerve terminals were abundant in the myenteric and submucous plexuses and the external muscle. Previous studies have identified two major classes of myenteric neurons in the small intestine of the mouse--those containing calretinin plus substance P, and those containing nitric oxide synthase (NOS) plus vasoactive intestinal peptide (VIP). Double-label studies showed that the vast majority of the calretinin/substance P neurons were cholinergic neurons, whereas only a small proportion of the NOS/VIP cells were cholinergic; the noncholinergic NOS/VIP neurons were motor neurons or interneurons, whereas the cholinergic NOS/VIP neurons appeared to be exclusively interneurons. In the small intestine, all of the 5-HT-loaded neurons and a subpopulation of the calbindin neurons were also cholinergic. In the large intestine, there was a pattern of overlaps similar to that found in the small intestine, except that in the large intestine approximately 25% of the calretinin cells were not cholinergic. Only approximately one third of the GABA-loaded neurons in the large intestine were cholinergic.
Large subpopulations of motor neurons and interneurons in the mouse small intestine are cholinergic neurons.
近期可获得的针对囊泡乙酰胆碱转运体（VAChT）和胆碱乙酰转移酶（ChAT）的抗血清能够显示外周胆碱能神经元，这使得在肠神经系统中对胆碱能神经元进行解剖学鉴定成为可能。在本研究中，我们对小鼠小肠和大肠中的胆碱能神经元进行了定位，并确定了哪些物质与胆碱能神经元共定位。
采用免疫组织化学单染和双染技术，对整装标本和冰冻切片进行检测，以研究小鼠小肠和大肠中胆碱能神经元的定位和化学编码。使用针对ChAT或VAChT的抗血清来鉴定胆碱能神经元。
在小肠和大肠中，肌间神经节和黏膜下神经节中均存在大量ChAT免疫反应性神经细胞体，肌间神经丛、黏膜下神经丛和外肌层中ChAT和VAChT免疫反应性神经末梢丰富。先前的研究已在小鼠小肠中鉴定出两类主要的肌间神经元——含有钙视网膜蛋白加P物质的神经元，以及含有一氧化氮合酶（NOS）加血管活性肠肽（VIP）的神经元。双标研究表明，绝大多数钙视网膜蛋白/P物质神经元是胆碱能神经元，而只有一小部分NOS/VIP细胞是胆碱能的；非胆碱能的NOS/VIP神经元是运动神经元或中间神经元，而胆碱能的NOS/VIP神经元似乎仅为中间神经元。在小肠中，所有5-羟色胺负载神经元和一部分钙结合蛋白神经元也是胆碱能的。在大肠中，存在与小肠中相似的重叠模式，只是在大肠中约25%的钙视网膜蛋白细胞不是胆碱能的。大肠中仅约三分之一的γ-氨基丁酸负载神经元是胆碱能的。
小鼠小肠中大量的运动神经元和中间神经元是胆碱能神经元。
