Previously, we reported that administration of prolactin (PRL) during the early luteal phase in sows increases plasma progesterone concentrations. In the current study, we searched for the mechanisms by which PRL exerts this luteotrophic effect. The objectives of the study were (1) to examine the effect of PRL and/or low-density lipoproteins (LDL) on progesterone production by porcine luteal ce...

TO THE EDITOR: Ferraris et al. (4) have recently reported an increase in anterior pituitary cell proliferation in 1-9-G129RhPRL (competitive prolactin receptor antagonist) -expressing transgenic mice compared to wild-type controls. In addition, they reported increased proliferation/decreased apoptosis in primary rat anterior pituitary cell cultures and somatolactotroph GH3 cells treated with 1-...

In the present study we searched for prolactin receptor (PRL-R) in porcine ovarian theca tissue (Tc) of small, medium and large follicles, as well as in early corpus luteum (ECL). The objectives of this investigation were: 1) comparison of the direct effect of PRL action on progesterone (P4) and estradiol (E2) secretion from Tc and ECL cells in culture with adequate effects caused by luteinizin...

Prolactin (PRL)-dependent rat pre-T Nb2 (Nb2-11) cell lines serve as a useful model for investigation of mechanisms underlying lactogen-mediated suppression of apoptosis. Glucocorticoids, such as dexamethasone (DEX), induce apoptosis in Nb2-11 cells; the addition of PRL abrogates the cytolytic actions of DEX in this model, presumably because of increased expression of survival genes. In the pre...

The pituitary hormone prolactin (PRL) exerts pleiotropic effects, which are mediated by a membrane receptor (PRLR) present in numerous cell types including adipocytes. Brown adipose tissue (BAT) expresses uncoupling proteins (UCPs), involved in thermogenesis, but also secretes leptin, a key hormone involved in the control of body weight. To investigate PRL effects on BAT, we used the T37i brown...

OBJECTIVE In vitro experiments and in vivo studies on rodents demonstrate that N-terminal 14, 15, 16, 17, and 18 kDa fragments prolactin-related vasoinhibin (PRL-V) of human PRL are natural inhibitors of neovascularization in the retina and elsewhere. These N-terminal PRL fragments belong to a family of peptides named vasoinhibins, which act as endogenous regulators of angiogenesis and vascular...

Much evidence suggests that prolactin (PRL) has an immunoregulatory function. Part of this evidence is that the receptors for PRL are present on lymphocytes. Probably the effects of PRL on cells of the immune system depend on the level and specific forms of PRL-R present on the target cells. Therefore, PRL-R expression at both protein and mRNA levels was examined during oestrous cycle, pregnanc...

Metabolic clearance rates (MCR) and production rates (PR) of prolactin (PRL) have been determined by the constant infusion to equilibrium technique in 11 normal subjects, 6 patients with hyperthyroidism, 4 patients with hypothyroidism, and 9 patients with hyperprolactinemia. PRL MCR was also determined tin four patients during dopamine infusion. Mean PRL MCR was 46 +/- 1 ml/min per m2 in women ...