RESPONSE OF RAT COLONIC MUCOSA TO A HIGH-FIBER DIET

Secreting lubricating mucins, colonic crypt goblet cells, contribute t o the intestinal protection against mechanical challenge. After feedin g germ-free (GF) and specific pathogen-free (SPF) AS/Ztm rats for 6 we eks, the proliferative response of colonic goblet cells to a commercia l bulky diet (37.1% fiber) was compared to that of a standard diet (4. 4% fiber). An increased uptake of the high fiber diet by GF rats signi ficantly augmented the capacity for mucin secretion as indicated by th e amount and length of crypts, crypt cells and mature goblet cells. Th e response of SPF rats was limited to a crypt elongation, generated by more crypt cells. In both study groups, the goblet cell replication a ctivity was similar to their controls. The increase in the mucin-secre ting capacity, induced by a constant mechanical challenge, highly sugg ests an improved intestinal protection.