High dietary fat, elevation of rat serum prolactin and mammary cancer.
We investigated the concept that the enhanced development of DMBA-induced mammary adenocarcinomas in rats fed a high fat diet might be mediated by prolactin via the hypothalamic-pituitary system rather than by a direct effect of a fat on the mammary gland itself. Prolactin levels in serum from female Sprague-Dawley rats fed high (20%) and low (0.5%) lard diets for 2 and 5 mo were measured by radioimmunoassay. The levels in rats at proestrus-estrus on high-lard diets were significantly higher (250 ng/ml) than those on a low lard diet (100 ng/ml). At metestrus-diestrus prolactin levels were approximately 50 ng/ml regardless of diet. Thus, the tumor-enhancing effect of a high fat diet may be indirect and mediated by neuro-hormonal changes in the hypothalamic centers controlling prolactin synthesis and secretion.
D015127:9,10-Dimethyl-1,2-benzanthracene; D000230:Adenocarcinoma / Q000139:chemically induced*; D000818:Animals; D004041:Dietary Fats / Q000008:administration & dosage; D004971:Estrus; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007457:Iodine Radioisotopes; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced*; D011247:Pregnancy; D011359:Proestrus; D011388:Prolactin / Q000097:blood*; D011863:Radioimmunoassay; D051381:Rats
D004041:Dietary Fats; D007457:Iodine Radioisotopes; D015127:9,10-Dimethyl-1,2-benzanthracene; D011388:Prolactin