The effects of glutamine on intestinal epithelial cell proliferation in parenterally fed rats

Background-Several papers have indicated that glutamine is a preferred fuel for the enterocyte and that it can increase intestinal epithelial cell pro liferation. Aims-To investigate the effects of glutamine on intestinal epithelial cell proliferation in the parenterally fed rat. Methods-Five groups of six rats were fed parenterally; a group of orally fe d rats was also studied. Crypt cell proliferation was studied after six day s using native mitoses in microdissected crypts and bromodeoxyuridine label ling. Results-No effect of treatment was seen on intestinal weight; however, the weights of the small intestine, caecum, and colon were all significantly he avier in the orally fed group than in the total parenteral nutrition groups (p<0.001). There was no effect of any of the glutamine treatments on mitot ic activity in the small intestine. In the colon there was a small increase in native mitoses with glutamine (p=0.03). There was also an indication of increased proliferative activity in the first fifth of the small intestine and colon with glutamine. Little effect of glutamine on bromodeoxyuridine labelling in either site was observed, but there was a small but significan t reduction in growth fi action of the colon of the glutamine treated group . The labelling distribution curve from sections and the mitotic distributi on curve obtained from crypt squashes showed a good correlation. Conclusion-Glutamine has a small, but significant effect on mitotic activit y but only in the colon. Modest effects on the distribution of labelled cel ls were also seen.