Berezin I, Huizinga J D, Daniel E E
Department of Biomedical Sciences, McMaster University Health Sciences Centre, Hamilton, Ont., Canada.
Can J Physiol Pharmacol. 1990 Nov;68(11):1419-31. doi: 10.1139/y90-216.
We have carried out a detailed ultrastructural study of the interstitial cells near the myenteric plexus of the canine colon and defined the structural characteristics which distinguish them from other resident non-neural cells. We have also examined the interconnections of these interstitial cells with nerves, the longitudinal muscle, and the circular muscle. In addition, we sought connections between interstitial cells of the myenteric plexus and those described earlier at the inner border of the circular muscle in proximal and distal colon. The interstitial cells of the myenteric plexus were structurally distinctive, and made gap junctions with one another and occasionally with smooth muscle. There seemed to be two subsets of these interstitial cells, one associated with the longitudinal muscle and the other with the circular muscle. Cells of both subsets were often close (less than or equal to 20 nm) to nerve profiles. The interstitial cells near the longitudinal muscle layer penetrated slightly into the muscle layer, but those near the circular muscle did not and neither set contacted the other. Moreover, interstitial cells of Cajal located near the myenteric plexus were never observed to contact those at the inner border of circular muscle. The interstitial cells of Cajal at the canine colon myenteric plexus are structurally organized to provide independent pacemaking activities for the longitudinal and adjacent circular muscle. Their dense innervation suggests that they mediate neural modulation of intestinal pacemaker activities. Moreover, they lack direct contacts with the interstitial cell network at the inner border of circular muscle, which is essential for the primary pacemaking activity of circular muscle. The structural organization of interstitial cells in canine colon is consistent with their proposed role in pacemaking activity of the two muscle layers.
我们对犬结肠肌间神经丛附近的间质细胞进行了详细的超微结构研究，并确定了将它们与其他驻留非神经细胞区分开来的结构特征。我们还研究了这些间质细胞与神经、纵行肌和环行肌之间的相互连接。此外，我们寻找肌间神经丛间质细胞与先前在近端和远端结肠环行肌内边界处描述的间质细胞之间的联系。肌间神经丛的间质细胞在结构上具有独特性，它们彼此之间以及偶尔与平滑肌形成缝隙连接。这些间质细胞似乎有两个亚群，一个与纵行肌相关，另一个与环行肌相关。两个亚群的细胞通常与神经纤维紧密相邻（小于或等于20纳米）。纵行肌层附近的间质细胞略微深入肌层，但环行肌附近的间质细胞则不深入，且两组细胞互不接触。此外，从未观察到肌间神经丛附近的 Cajal间质细胞与环行肌内边界处的间质细胞接触。犬结肠肌间神经丛处的 Cajal间质细胞在结构上有组织地为纵行肌和相邻的环行肌提供独立的起搏活动。它们密集的神经支配表明它们介导肠道起搏活动的神经调节。此外，它们与环行肌内边界处的间质细胞网络缺乏直接接触，而这对于环行肌的主要起搏活动至关重要。犬结肠间质细胞的结构组织与其在两层肌肉起搏活动中所提出的作用一致。
