All these other hormones are stimulated by the hypothalamus hormone but prolactin is inhibited by the release of our prolactin inhibitory hormone. So the hypothalamus releases the prolactin inhibitory hormone or PIF. PIH, this hormone basically can be replaced with factor. So we have prolactin inhibitory factor. That's why this is also known as PIF and this actually doesn't stimulate, it inhibits the release of prolactin. Now, as we'll see in the next several lectures prolactin is involved in enabling milk production in females.