CELLULAR DYNAMICS IN THE INTESTINAL MUCOSA: THE EFFECT OF IRRADIATION ON EPITHELIAL MATURATION AND MIGRATION

Although irradiation of the duodenum of rats inhibits mitosis in the crypts and halts the normal passage of cells up the villi, the maturation of goblet cells is not affected. The ripening of mucous elements while arrested in the crypts, where they form, instead of during their migration along the villi, results in the so called mucous change, which has hitherto been considered a form of degeneration. During the phase of recovery, the reestablishment of normal migration and desquamation is marked by the appearance of strata of fully formed goblet cells at successive levels out along the villi. It is suggested that some gastrointestinal disturbances known to occur in spontaneous and experimental vitamin deficiency might be explained in terms of aberrations in the cellular replacement of the intestinal mucosa.