Huizinga Jan D, Hussain Amer, Chen Ji-Hong
McMaster University, Farncombe Family Digestive Health Research Institute, Department of Medicine, Division of Gastroenterology, Hamilton, ON, Canada.
Adv Exp Med Biol. 2022;1383:205-212. doi: 10.1007/978-3-031-05843-1_19.
The musculature of the gastrointestinal tract is a vast network of collaborating excitable cell types. Embedded throughout are the interstitial cells of Cajal (ICC) intertwined with enteric nerves. ICC sense external stimuli such as distention, mediate nerve impulses to smooth muscle cells, and provide rhythmic excitation of the musculature. Neural circuitry involving both the intrinsic and extrinsic autonomic nervous systems, in collaboration with the ICC, orchestrate an array of motor patterns that serve to provide mixing of content to optimize digestion and absorption, microbiome homeostasis, storage, transit, and expulsion. ICC are specialized smooth muscle cells that generate rhythmic depolarization to the musculature and so provide the means for peristaltic and segmenting contractions. Some motor patterns are purely myogenic, but a neural stimulus initiates most, further depolarizing the primary pacemaker cells and the musculature and/or initiating transient pacemaker activity in stimulus-dependent secondary ICC pacemaker cells. From stomach to rectum, ICC networks rhythmically provide tracks along which contractions advance.
胃肠道的肌肉组织是一个由相互协作的可兴奋细胞类型构成的庞大网络。其中遍布着与肠神经交织在一起的 Cajal 间质细胞（ICC）。ICC 感知诸如扩张等外部刺激，将神经冲动传导至平滑肌细胞，并为肌肉组织提供节律性兴奋。涉及内在和外在自主神经系统的神经回路，与 ICC 协作，精心编排一系列运动模式，这些运动模式有助于使内容物混合以优化消化和吸收、微生物群稳态、储存、运输及排出。ICC 是专门的平滑肌细胞，可产生向肌肉组织的节律性去极化，从而为蠕动和分段收缩提供方式。一些运动模式纯粹是肌源性的，但大多数由神经刺激引发，进一步使初级起搏细胞和肌肉组织去极化，和/或在依赖刺激的次级 ICC 起搏细胞中引发瞬时起搏活动。从胃到直肠，ICC 网络有节律地提供收缩推进的轨迹。
