Canine mammary tumours (CMTs) represent nearly half of all tumours in female dogs and some 50% have malignant behaviour. Simple epithelial carcinomas have shorter disease free periods after surgery and a higher reduction of the proliferation index reduction after antiprogestin aglepristone treatment in vivo related to the expression of progesterone receptors (PR). These findings make simple car...

Progesterone receptor (PR), a member of the nuclear receptor superfamily, is a key regulator of several processes in reproductive function. We have studied the dynamics of the interaction of PR with a natural target promoter in living cells through the use of fluorescence recovery after photobleaching (FRAP) analysis and also have characterized the dynamics of the interaction of PR with the mou...

Social isolation rearing (isolated condition, IC) is used as a model of early life stress in rodents. Rats raised in this condition are often compared to rats raised in an environmentally enriched condition (EC). However, EC rats are repeatedly exposed to forced novelty, another classic stressor in rodents. These studies explored the relationship between cocaine self-administration and glucocor...

Gravidin is a potent phospholipase A2 inhibitor that may contribute to the maintenance of human pregnancy. The aims of this study were to determine firstly, the site of gravidin synthesis within placental membranes and secondly, whether the antiprogestin compound, RU486, regulates synthesis. Membrane explants were taken from placentae, dissected and cultured in the presence of RU486, progestero...

Glucocorticoids stimulate the intestinal absorption of Na(+) and water partly by regulation of the Na(+)/H(+) exchanger 3 (NHE3). Previous studies have shown both genomic and nongenomic regulation of NHE3 by glucocorticoids. Serum and glucocorticoid-inducible kinase 1 (SGK1) has been shown to be part of this cascade, where phosphorylation of NHE3 by SGK1 initiates the translocation of NHE3 to t...

Fibroblast growth factor-3 (FGF-3) is a crucial developmental regulator. Aberrant activation of this gene by mouse mammary tumor virus insertion results in pregnancy-responsive mammary tumorigenesis. To characterize better FGF-3 function in postnatal mammary gland development and cancer initiation/progression, we used a mifepristone (RU486)-inducible regulatory system to express conditionally F...

The pregnane X receptor (PXR) mediates the induction of various genes by xenobiotics, including several ATP-binding cassette transporters. PXR is also activated by bile acids likely to prevent their accumulation to toxic levels; however, the role of PXR in the regulation of MRP3, an important bile acid efflux transporter, has not been elucidated. The impact of PXR activators on the hepatic expr...

1. The influence of progesterone on the activity of atrial natriuretic factor (ANF) on rat myometrial motor activity was determined in vitro. 2. ANF inhibited the tension development by myometrium from cycling or oestrogen-treated rats in a dose-dependent manner; maximal inhibition was 100%. 3. Injections of progesterone into rats inhibited the tocolytic activity of ANF in a dose and time-depen...