THE EFFECTS OF NEONATAL ANDROGENIZATION ON MAMMARY-GLAND MITOTIC RATE AND SUSCEPTIBILITY TO CARCINOGEN-INDUCED MAMMARY DYSPLASTIGENESIS AND TUMORIGENESIS IN LEW-MAI RATS
- 1 January 1980
- journal article
- research article
- Vol. 99 (2) , 463-474
Abstract
The influence of neonatal testosterone propionate treatment (androgenization) on mammary gland mitotic rate (MR) and susceptibility to 7,12-dimethylbenz(.alpha.)anthracene (DMBA) carcinogenesis was studied in female LEW/Mai rats. Mammary gland MR in androgenized rats was significantly lower than MR in normal rats at all ages studied. Treatment of androgenized rats with DMBA resulted in a significant increase in mammary gland MR in comparison with untreated androgenized rats. MR in DMBA-treated androgenized rats was similar to MR in DMBA-treated normal rats at most intervals after the introduction of the carcinogen. Although mammary epithelial MR in androgenized rats was significantly lower than that of normal rats of comparable age, no evidence of a decrease in susceptibility of mammary epithelium in androgenized rats to DMBA carcinogenesis was found. Androgenized rats had a higher incidence of DMBA-induced mammary dysplasias, with no change in their morphologic or histologic features, than did normal rats. There was no change in the incidence, latency or histopathologic appearance of DMBA-induced mammary tumors in androgenized vs. normal rats.This publication has 15 references indexed in Scilit:
- LONG-TERM EFFECTS OF NEONATAL TREATMENT WITH PROGESTERONE, ALONE AND IN COMBINATION WITH ESTROGEN, ON MAMMARY-GLAND AND REPRODUCTIVE-TRACT OF FEMALE BALB-CFC3H MICE1977
- Neonatal modification of endocrine functions and mammary carcinogenesis in the ratBritish Journal of Cancer, 1976
- IMPORTANCE OF MAMMARY-GLAND DNA-SYNTHESIS ON CARCINOGEN-INDUCED MAMMARY TUMORIGENESIS IN RATS1976
- Effects of exposure of neonatal mice to 17beta-estradiol on subsequent age-incidence and morphology of carcinogen-induced mammary dysplasia.1975
- Exposure of neonatal mice to steroids: Longterm effects on the mammary gland and other reproductive structuresJournal of Steroid Biochemistry, 1975
- Effect of neonatally administered estrogen or prolactin on normal and neoplastic mammary growth and serum estradiol-17 beta level in rats.1974
- Brief Communication: Frequency of Mammary Cell Division in Relation to Age: Its Significance in the Induction of Mammary Tumors by Carcinogen in Rats2JNCI Journal of the National Cancer Institute, 1974
- Effects of neonatally administered sex steroids on 7,12-dimethylbenz(a)anthracene-induced mammary neoplasia in rats.1973
- Serum and Pituitary Prolactin, LH, and FSH in Androgenized Female and Normal Male Rats treated with Various Doses of Estradiol BenzoateNeuroendocrinology, 1973
- Effect of androgenisation on the development of mammary tumours in rats induced by the oral administration of 9,10-dimethyl-1,2-benzanthraceneBritish Journal of Cancer, 1965