ANTI-C-KIT PROTEIN IMMUNOREACTIVE CELLS CORRESPONDING TO THE INTERSTITIAL-CELLS OF CAJAL IN THE GUINEA-PIG SMALL-INTESTINE

Interstitial cells of Cajal (ICC) of the guinea-pig small intestine we re studied with whole-mount preparations by using the zinc iodide-osmi c acid method (ZIG) and immunohistochemistry for vimentin and c-kit re ceptor tyrosine kinase, and by electron microscopy. The myenteric ICC visualized with ZIO staining are immunopositive to both anti-c-kit ant ibody (ACK-2) and anti-vimentin antibody (V9), and constitute an indep endent cellular network from the myenteric plexus. Those cells are cha racterized by many mitochondria, abundant intermediate filaments, and surface cell membranes not covered with a basal lamina. They are conne cted with each other by gap junctions at tips of the cytoplasmic proce sses. It is concluded that the myenteric ICC of the guinea-pig intesti ne are fibroblast-like cells and that they correspond to the c-kit exp ressing cells regarded as the intestinal pacemaker.