interference with the organisms endocrine balance ( gonadectomy on day 25 of life , hypophysectomy on day 50 , a combination of both these operations , administration of testosterone or oestradiol ) demonstrates that the sexually differentiated enzyme activities may be classified as androgen or oestrogen dependent , the respective sex hormone acting either in an inductive or repressive manner .
C0014136
endocrine
C0020632
hypophysectomy