DIFFERENT DOSE-RESPONSE RELATIONSHIPS IN THE INDUCTION OF DIFFERENT TYPES OF COLONIC TUMORS IN WISTAR RATS BY 1,2-DIMETHYLHYDRAZINE

  • 1 January 1983
    • journal article
    • research article
    • Vol. 74  (1) , 21-27
Abstract
Four groups of 21 male Wistar rats were given weekly s.c. injections of 1,2-dimethylhydrazine at a dose of 20 mg/kg body weight for 2, 4, 6 and 8 wk, respectively, and 7 animals of each group were killed in weeks 24, 32 and 40. This treatment induced a clear dose-related increase in the total number of colonic carcinomas. The number of tubular adenocarcinomas, which were mostly located in the descending colon, was clearly dose-related, whereas the number of signet ring cell carcinomas, which developed in the ascending colon, was apparently dose-independent.