Effect of dietary fat, antiestrogen, and antiprolactin on the development of mammary tumors in rats
Chan, P.C.; Cohen, L.A.
Journal of the National Cancer Institute 52(1): 25-30
1974
ISSN/ISBN: 0027-8874 PMID: 4810966 Document Number: 78736
Female Sprague-Dawley rats 50 days old, fed on a high-fat (HF) synthetic diet and given 5 or 10 mg 7,12-dimethylbenzanthracene (DMBA) by stomach tube, developed mammary tumours earlier and in greater numbers than rats on a low-fat (LF) diet. Average growth rate, based on bodyweight, was comparable in both groups. When rats treated with DMBA and on HF and LF diets were given the antiprolactin drug CB-154 or the antioestrogen drug U11,100 A, tumour development was decreased in extent and rate by the antioestrogen, but the differential incidence of tumours in rats on HF diet remained higher than that in rats on LF diet. The antiprolactin drug completely suppressed the formation of all palpable mammary tumours at the 5 mg DMBA dose in rats on HF or LF diet; at the 10 mg DMBA dose tumour incidence was reduced by the antiprolactin drug but there was no differential effect of dietary fat.