It is well known that ovarian function is regulated by hypothalamic-pituitary-ovarian hormones. However, although several histological studies have described the autonomic innervation of the ovary, the involvement of these autonomic nerves in ovarian function is unclear. Recently, it has been shown that both the superior ovarian nerve (SON) and the ovarian nerve plexus (ONP) induce vasoconstrictor activity by activation of alpha 1-adrenoceptors, whereas the SON, but not the ONP, inhibits ovarian estradiol secretion by activation of alpha 2-adrenoceptors. Furthermore, reflex activation of these ovarian nerves by noxious cutaneous stimulation of the rat hindpaw results in ovarian vasoconstriction and inhibition of estradiol secretion. Thus, in addition to long-term regulation of ovarian function by hormones, ovarian autonomic innervation may be involved in rapid regulation of ovarian function by responding to either internal or external environmental changes.