Gamma-glutamyltransferase activity in mammary gland of pregnant rats and its regulation by ovarian hormones, prolactin and placental lactogen.
Ovariectomy and ovariectomy plus hysterectomy on day 18 of pregnancy increased gamma-glutamyltransferase activity in the mammary gland. The withdrawal of progesterone and the subsequent release of prolactin are responsible for the rise in enzyme activity. Rat placental lactogen in the absence of prolactin and progesterone is able to induce gamma-glutamyltransferase activity.
D000818:Animals; D002369:Castration; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D008321:Mammary Glands, Animal / Q000187:drug effects / Q000201:enzymology*; D010928:Placental Lactogen / Q000494:pharmacology*; D011247:Pregnancy; D011374:Progesterone / Q000494:pharmacology*; D011388:Prolactin / Q000494:pharmacology*; D051381:Rats; D005723:gamma-Glutamyltransferase / Q000378:metabolism*
D011374:Progesterone; D004958:Estradiol; D011388:Prolactin; D010928:Placental Lactogen; D005723:gamma-Glutamyltransferase