Ovaries Endocrine Function - Anatomy & Physiology

Reproductive hormones tend to have short half lives and act in minute quantities. They bind to specific receptors on their target organs. Oestrus Cycle

Hormones of the Ovaries

Hormone	Production and Regulation	Action
Oestrogen	GnRH from the Hypothalamus causes FSH secretion from the Pituitary Gland which stimulates the developing follicles in the ovary to secrete this hormone.	Promotes development of mammary tissue and is vital for thickening of the endometrium prior to implantation. Oestrogens regulate the Oestrus Cycle.
Progesterone	This is produced in the Corpus Luteum after ovulation, and also the Placenta during pregnancy.	Progesterone is sometimes known as the hormone of pregnancy. It converts the endometrium to its secretory stage to prepare for implantation, reduces the immune response within the uterus to allow for acceptance of the conceptus, and decreases contractility of the smooth muscle.
Inhibin	GnRH from the Hypothalamus causes FSH secretion from the Pituitary Gland which stimulates the Granulosa cells.	Inhibits FSH secretion.
Relaxin	This is produced by the Corpus Luteum towards the end of pregnancy as a result of fetal ACTH production.	Relaxes the cervix and pelvic ligaments in preparation for parturition.
Oxytocin	Oxytocin is mainly produced by the Hypothalamus and secreted by the Pituitary Gland, however in some species including primates and ruminants it is produced by the Corpus Luteum.	In addition to allowing Milk let-down and promoting uterine contractions, oxytocin works along with oestrogen to induce endometrial production of PGF-2a resulting in regression of the Corpus Luteum.