Liu L W, Farraway L, Berezin I, Huizinga J D
Intestinal Disease Research Programme, Department of Biomedical Sciences, HSC-3N5C, McMaster University, 1200 Main Street West, Hamilton, Ontario, Canada, L8 N 3Z5.
Cell Tissue Res. 1998 Oct;294(1):69-79. doi: 10.1007/s004410051157.
The network of interstitial cells of Cajal associated with Auerbach's (myenteric) plexus in the canine colon was investigated to determine its role in facilitating communication between circular and longitudinal muscle layers. Electrical coupling between the muscle layers was demonstrated by propagating extracellularly evoked electrotonic pulses from circular muscle cells to nearby longitudinal muscle cells. The likelihood of cytoplasmic continuity across Auerbach's plexus was further demonstrated by the ability of neurobiotin to spread between the interstitial cells and the circular and longitudinal muscle cells. Importantly, direct neurobiotin spread between circular and longitudinal muscle cells was not observed even when they were in close proximity as determined by confocal microscopy. When neurobiotin did spread across the two muscle layers, the intervening interstitial cells were always neurobiotin-positive. In regions where circular and longitudinal muscle cells approach each other closely, electron microscopy revealed the presence of close appositions between interstitial cells and smooth muscle cells. Gap junctions between interstitial cells and smooth muscle cells of both layers, as judged by electron microscopy, were extremely rare. Neither gap junctions nor close appositions were observed between longitudinal and circular muscle cells. The special arrangement for electrotonic coupling across Auerbach's plexus through interstitial cells of Cajal suggests controlled coupling between the two muscle layers, explaining the preservation of their distinct electrical activities.
对犬结肠中与奥尔巴赫（肌间）神经丛相关的 Cajal 间质细胞网络进行了研究，以确定其在促进环行肌层和纵行肌层之间通讯中的作用。通过将细胞外诱发的电紧张脉冲从环行肌细胞传播到附近的纵行肌细胞，证明了肌层之间的电耦合。神经生物素在间质细胞与环行肌细胞和纵行肌细胞之间扩散的能力，进一步证明了穿过奥尔巴赫神经丛的细胞质连续性的可能性。重要的是，即使通过共聚焦显微镜确定环行肌细胞和纵行肌细胞彼此靠近，也未观察到神经生物素在它们之间直接扩散。当神经生物素确实在两个肌层之间扩散时，其间的间质细胞总是神经生物素阳性。在环行肌细胞和纵行肌细胞彼此紧密靠近的区域，电子显微镜显示间质细胞与平滑肌细胞之间存在紧密贴附。通过电子显微镜判断，两层间质细胞与平滑肌细胞之间的缝隙连接极其罕见。在纵行肌细胞和环行肌细胞之间未观察到缝隙连接或紧密贴附。通过 Cajal 间质细胞穿过奥尔巴赫神经丛进行电紧张耦合的特殊排列表明，两个肌层之间存在受控耦合，这解释了它们独特电活动的保留。
