[Regulation of cell renewal in the gastrointestinal mucosa (author's transl)]

The renewal of the digestive mucosa is the most efficient process assuming the maintenance of the gastrointestinal barrier. The mucous and absorptive cells, born in the proliferative zone, are migrating to the surface and they extrude duirng meals, living 4 to 6 days. Hyperphagia, pregnancy, lactation and intestinal resection induce a hypertrophic state. Fasting, ageing, germ free status provoke a hypoplasia. The ulcerogenic and antimitotic drugs decrease the proliferative activity. The gastrointestinal cell renewal is controlled by hormonal, vitaminic and nervous agents. Gastrin and growth hormone are the major trophic factors, secretom amd cprtocpsteroids act as antitrophic agents. The vitamins A, D and B12, and the nervous transmittors participate in the feed back control assuming a steady state between proliferation and extrusion. Chalones and immunologic factors are probably the most important but unknown inhibitors. The pathological events concerned with abnormal renewal are peptic ulcer, atrophic gastritis, intestinal villous atrophy and digestive cancer.