The secretion of prostaglandin F from the autotransplanted uterus of the ewe.

Prostaglandin (PG) F-2\g=a\is involved in a number of reproductive functions, including luteolysis (Goding, 1974) and menstruation (Pickles, Hall, Best & Smith, 1965). Luteolysis in sheep is controlled by a local feedback loop operating between the uterus and the corpus luteum, and menstruation in primates is also directly controlled by the ovarian steroid hormones. A fuller knowledge of how these hormones influence the endometrium to produce and release PGF-2\g=a\should lead to a better understanding of both luteolysis and menstruation. In the present report we have examined the effects of oestradiol-17ß and progesterone on the ability of the autotransplanted sheep uterus to release PGF into the uterine vein.