Effect of the prostaglandin synthetase inhibitor indomethacin on 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis in rats fed different levels of fat.
The effect of the prostaglandin synthetase inhibitor indomethacin on the dietary fat enhancement of 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis has been examined in female Sprague-Dawley rats. Rats were fed either a normal-fat or high-fat diet (5 or 18% corn oil, respectively) with or without 0.004% indomethacin, starting 3 days after a single intragastric intubation of 5 mg 7,12-dimethylbenz(a)anthracene. Results of this experiment demonstrated that indomethacin completely blocked the stimulatory effect of fat on tumorigenesis, as measured by a decreased tumor incidence, a decreased number of tumors per group, a decreased tumor size, and an increased latency. No effect of indomethacin was observed in rats fed the normal-fat diet. These data suggest that at least part of the stimulatory effect of polyunsaturated fat on 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis may be mediated through an increased synthesis of prostaglandins.
D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D001551:Benz(a)Anthracenes; D001835:Body Weight / Q000187:drug effects; D003345:Corticosterone / Q000097:blood; D016861:Cyclooxygenase Inhibitors; D004041:Dietary Fats / Q000008:administration & dosage* / Q000494:pharmacology; D005260:Female; D007213:Indomethacin / Q000494:pharmacology*; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced*; D051381:Rats; D011919:Rats, Inbred Strains
D001551:Benz(a)Anthracenes; D016861:Cyclooxygenase Inhibitors; D004041:Dietary Fats; D015127:9,10-Dimethyl-1,2-benzanthracene; D003345:Corticosterone; D007213:Indomethacin