Flow cytometric analysis of oestrogen receptors in relation to histopathologic characteristics of DMBA-induced mammary tumours in rats.
Experimental DMBA (7,12-dimethylbenzanthracene)-induced mammary tumours in Sprague-Dawley rats are studied. Percentages of the distinct types of adenocarcinomas (Stevens et al. 1965) were as follows: type A (poorly-differentiated), 8.8%; type B (well-differentiated), 65.5%; type C (atrophic), 15.5% and type D (secretory), 5.4%. 51% of the mammary adenocarcinomas were seen to be positive to oestradiol receptors by means of flow cytometry; type A adenocarcinomas were found to be the most frequent positive tumours (88.9% positive cases) whereas the last adenocarcinomas to appear (type D) were negative. These results suggest that the oestradiol-sensitivity of DMBA-induced mammary adenocarcinomas decreases as the post tumour-induction period lengthens.
Peña
L
L
Complutense University of Madrid, Veterinary School, Department of Animal Pathology II, Spain.
Flores
J M
JM
González
M
M
Pizarro
M
M
Gómez
M
M
D015127:9,10-Dimethyl-1,2-benzanthracene; D000230:Adenocarcinoma / Q000139:chemically induced / Q000737:chemistry / Q000473:pathology*; D000818:Animals; D005260:Female; D005434:Flow Cytometry; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000737:chemistry / Q000473:pathology*; D008854:Microscopy, Electron; D051381:Rats; D011919:Rats, Inbred Strains; D011959:Receptors, Estradiol / Q000032:analysis*
D011959:Receptors, Estradiol; D015127:9,10-Dimethyl-1,2-benzanthracene