To evaluate the PRL secretory mechanism in patients with PRL-secreting adenoma (PRL-oma), plasma PRL responses to dopamine (DA) were studied in these cases and in normal subjects. Plasma PRL values showed clear decreases during the infusion of DA (5 micrograms/kg/min for 90 min) in both 6 normal and 7 PRL-oma subjects (%decrease: 43.8 +/- 3.9% vs. 53.9 +/- 5.6%; NS) and postinhibitory increases...

Prolactin (PRL) is involved in numerous biological processes in peripheral tissues and the brain. Although numerous studies have been conducted to elucidate the signal transduction pathways associated with the PRL receptor, very few have examined the role of ion conductances in PRL actions. We used the patch-clamp technique in "whole cell" configuration and microspectrofluorimetry to investigat...

Phosphatase found in regenerating liver (PRL)-1, PRL-2, and PRL-3 [also known as PTP4A1, PTP4A2, and PTP4A3, respectively] constitute a unique family of putative protein tyrosine phosphatases (PTPs) modified by farnesylation. PRL-3 is amplified and its message is up-regulated in colorectal carcinoma metastases. Its ectopic expression promotes invasive and metastatic properties, supporting a cau...

Prolactin (PRL) is involved in the regulation of immune functions under normal and pathological conditions. Trauma-hemorrhage (T-H) produces profound immunosuppression in male mice but not in proestrus female mice. Administration of PRL in males after T-H, however, restores immune functions. In this study, PRL(+/+) and transgenic (PRL(-/-)) male and female mice were used to assess immune suppre...

The present study analyzed the expression and clinical role of the protein of regenerating liver (PRL) phosphatase family in ovarian carcinoma. PRL1-3 mRNA expression was studied in 184 tumors (100 effusions, 57 primary carcinomas, 27 solid metastases) using RT-PCR. PRL-3 protein expression was analyzed in 157 tumors by Western blotting. PRL-1 mRNA levels were significantly higher in effusions ...

Human scalp skin and hair follicles (HFs) are extra-pituitary sources of prolactin (PRL). However, the intracutaneous regulation of PRL remains poorly understood. Therefore we investigated whether well-recognized regulators of pituitary PRL expression, which also impact on human skin physiology and pathology, regulate expression of PRL and its receptor (PRLR) in situ. This was studied in serum-...

Development and activation of immune cells are submitted to hormonal influences, as illustrated by the roles of corticosteroids in thymus, pregnancy-related estrogens in B-cell development, or prolactin (PRL) on T-cell generation and function. We have analyzed the putative role of PRL in B lymphopoiesis and differentiation. We chose as an experimental model the interleukin (IL)-3 dependent BaF-...

Prolactin (PRL) is a 23-kDa hormone produced by the pituitary and extrapituitary sites. The main target of PRL is the breast, where it affects cellular growth, differentiation, and milk production. Recent evidence suggests that locally produced PRL plays a role in breast tumorigenesis. Our objective was to examine PRL synthesis/release in different tissues of the human breast and determine the ...

Prolactin (PRL) is implicated in the modulation of spontaneous rapid eye movement sleep (REMS). Previous models of hypoprolactinemic animals were characterized by changes in REMS, although associated deficits made it difficult to ascribe changes in REMS to reduced PRL. In the current studies, male PRL knock-out (KO) mice were used; these mice lack functional PRL but have no known additional def...

Immunoreactive prolactin (ir-PRL) in rat brain has been consistently documented. However, the identity of this ir-PRL is controversial. Ir-PRL is defined by its ability to bind to PRL antibodies. All previous studies of brain ir-PRL have used polyclonal antibodies, at least one of which apparently crossreacts with a portion of the proopiomelanocortin molecule. To begin to define the epitopes co...