The Morphologic Study of Vitamin A(Retinol) on 1, 2-Dimethylhydrazine Induced Colon Carcinogenesis in the Rats

Ki Sook Hong

Corresponding author: Ki Sook Hong. Department of Pathology, College of Medicine, Ewha Womans University

Copyright ⓒ 1989. Ewha Womans University School of Medicine. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Published Online: Jul 24, 2015

Abstract

Induction of intestinal tumor by subcutaneous injection of 1, 2-dimethylhydrazine(DMH), 20 mg/kg/week, during 20 weeks was studied in rats fed by vitamin A(retinol) 50 µg, 500 µg/day.

Mucosal epithelial cell hyperplasia and mitosis in one crypt was not significantly inhibited by vitamin A administration(P>0.05). In electron microscopic findings, the cytoplasmic vacuoles were decreased in DMH+vitamin A-treated rats than DMH only. Dysplasia of the colonic mucosa in DMH+vitamin A-treated group were more slowly developed than DMH-treated rats. In DMH-treated rats the tumors were early detected after 14 weeks, but in DMH+vitamin A-treated groups were seen after 20 weeks.

All these findings suggest that vitamin A can effectively prevent cytotoxicity of carcinogen in early phase, but can not prevent carcinogenesis in late phase.