[Experimental cancerogenesis. Stimulation of ornithine decarboxylase of the colonic mucosa in vitamin A-deficient rats by sodium desoxycholate].

During a state of pure vitamin A deficiency, without any clinical manifestations, in colonic mucosa: ornithine decarboxylase activity is already stimulated, in deficient animals, by instillation of NaCl 9%. Sodium deoxycholate further enhances and markedly protracts the enzyme activity, as compared to normal rats. These results lead to the conclusion that vitamin A deficiency is a state of special sensibility to the promoter action. Retinol is hence physiologically necessary for natural resistance of intestinal cells against chemically induced tumor promotion.