Secretory Rate 8 Female 6 Rats 6 animal experiment 6 rat 6 Animal 4 Animals 4 Pregnancy 4 Prolactin 4 Prostaglandins E 4 Prostaglandins F 4 in vitro study 4 indometacin 4 prolactin 4 prolactin release 4 prostaglandin e2 4 4 methylhistamine 2 Animalia 2 Cattle 2 Culture Media 2 Diphenhydramine 2 Eflornithine 2 Estrus 2 Follicle Stimulating Hormone 2 Gonadotropin-Releasing Hormone 2 Histamine 2 Indomethacin 2 Injections, Intraventricular 2 Lactation 2 Luteinizing Hormone 2