Endocrine Abstracts

Prolactin is produced by pituitary lactotrophic cells and by several extrapituitary tissues, including immune cells and the endometrium in man. It has a wide range of actions at different sites, and hyperprolactinaemia and prolactinomas give rise to common clinical problems. The human prolactin gene contains six exons, with two distinct promoters that direct pituitary or extra-pituitary transcription respectively. The pituitary-specific promoter extends over 5000 base-pairs an...

Today prolactin (PRL) has been demonstrated to regulate more then 300 different biological functions, including metabolism during lactation and in subjects with hyperprolactinemia. However, the mechanisms for how PRL regulates the adipose tissue in humans and rodents have remained unclear. We recently reported PRL receptor (PRLR) expression in the adipose tissue of lactating and in PRL-transgenic mice. These results suggest PRLR-mediated effects in adipose tissue. However, to ...

In the human endometrium, the postovulatory rise in ovarian progesterone results in the influx of distinct local immune cells and induces the coordinated expression of certain gene sets that initially define a limited period of uterine receptivity and subsequently control differentiation of the stromal compartment (decidualisation). Decidualisation is critical for trophoblast invasion and the formation of a haemochorial placenta. Pathologically, a spectrum of reproductive diso...

PRL has long been recognized as a hormone that regulates both cell proliferation and differentiation in the mammary gland. Current theory proposes that it is the coexisting steroidal environment which dictates whether PRL is mainly proliferative, as it is during pregnancy, or mainly differentiative, as it is during lactation. While major changes in the steroidal environment may contribute to a shift in response by the mammary gland, other tissues which show both responses to P...