MORPHOLOGICAL EVIDENCE FOR A CECOCOLONIC JUNCTION IN MAN AND FUNCTIONAL IMPLICATIONS

The region above, below and in front of the ileocecal valve opening has been studied in man using both light and electron microscopy. A cecocolonic junction. comprising the colonic basal portion of the ileocecal valve, could be demontrated in man, due to specific anatomy of the inner portion of the circular muscle. This muscle was arranged in anastomosing cord, richly innervated and enveloped by elastic fibers. Its smooth muscle cells were characterized by extremely wide sarcoplasmic cisternae and cell to cell juncrtions, numerous caveolae and large amounts of glycogen. Interstitial cells were rarely found. This junction might be considered responsible for (1) ileal flow accomodation (2) colonic active movements (3) ileocecal valve closing and opening