Session: S56-Central Regulation and Actions of Prolactin
Room 301 (Moscone Center)
Prolactin (PRL) identified by its ability to stimulate mammary gland development and lactation is mainly secreted by lactotroph cells of the anterior pituitary. It is usually accepted that pituitary PRL secretion is positively and negatively regulated, but it is mainly controlled by inhibitory factors originating in the hypothalamus, the most important of which is dopamine. Unlike rodents, the role of PRL in human function is unclear, largely because no disruptive mutations of human PRL or the human PRLR have ever been identified in reproductive pathologies. However, hyperprolactinemia has been known to cause infertility by anovulation but the mechanism underlying this has remained enigmatic. This disease is of high incidence and the most common cause of hypogonadotropic amenorrhea. Using a mouse model of hyperprolactinemia, we demonstrated that kisspeptin neurons act as the missing link between hyperprolactinemia and GnRH deficiency. We will summarize our current knowledge about PRL signaling and its role in reproduction.