title: Characterization of interstitial cells of Cajal in the subserosal layer of the guinea-pig colon.
abstract: Interstitial cells of Cajal in the subserosa (ICC-SS) of the guinea-pig proximal colon were studied by immunohistochemistry for c-Kit receptors and by transmission electron microscopy. These cells were distributed within a thin layer of connective tissue space immediately beneath the mesothelium and were multipolar with about five primary cytoplasmic processes that divided further into secondary and tertiary processes to form a two-dimensional network. Ultrastructural observations revealed that ICC-SS were connected to each other via gap junctions. They also formed close contacts and peg-and-socket junctions with smooth muscle cells. Three-dimensional analysis of confocal micrographs revealed that the cytoplasmic processes of ICC-SS had contacts with interstitial cells in the longitudinal muscle layer. Taking account of the location and peculiar arrangement of the ICC-SS and the main functions of the proximal colon, i.e. the absorption and transport of fluids, we suggest that the superficial network of ICC-SS acts as a stretch receptor to detect circumferential expansion and swelling of the colon wall and triggers the contraction of the longitudinal muscle to accelerate the drainage of fluids from the colon.
authors.affiliation: Laboratory of Histology and Neuroscience, Department of Health Science and Social Welfare, Faculty of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Aranishi
authors.forename: Yumi
authors.initials: Y
authors.lastname: Kunisawa
authors.forename: Terumasa
authors.initials: T
authors.lastname: Komuro
mesh_terms: D000818:Animals; D003106:Colon / Q000502:physiology / Q000648:ultrastructure*; D005260:Female; D017629:Gap Junctions / Q000648:ultrastructure*; D006168:Guinea Pigs; D007413:Intestinal Mucosa / Q000648:ultrastructure*; D046529:Microscopy, Electron, Transmission; D009130:Muscle, Smooth / Q000648:ultrastructure*; D012704:Serous Membrane / Q000166:cytology