Influence of Prolactin and Growth Hormone on Rat Mammary Tumors Induced by N-Nitrosomethylurea

摘要: Abstract The effects of hypophysectomy and prolactin-suppressing drugs on the growth mammary tumors induced in Sprague-Dawley rats by N-nitrosomethylurea dimethylbenz(a)anthracene were compared. influence ovine prolactin hormone administration N-nitrosomethylurea-induced was also studied hypophysectomized animals. After hypophysectomy, all 13 underwent regression, as did ten 12 dimethylbenz(a)anthracene. There no new tumors. Pergolide mesylate, a long-acting ergoline derivative, given dose 80 μg twice daily s.c. injection for 28 days. Only three regressed, while four became static. However, only two developed pergolide-treated rats, compared to 11 untreated controls. Bromocriptine at times pergolide dose, even less effective; one 16 static, eight appeared rats. In contrast, dimethylbenz(a)anthracene-induced regressed during therapy, there tumor among Prolactin, 1 mg 7 days injection, another bearing tumors, commencing after hypophysectomy. Regression five borne reversed but resumed when treatment stopped. other animals arrested without regrowth; sixth inpalpable. All these six grew rapidly hormone, 2 daily, administered addition prolactin.