Background To attain whether the effects of low and high doses of estrogen progesterone luteinizing hormone (LH) and follicle stimulating hormone (FSH) in acute and chronic administration were related to oxidant and antioxidant parameters in rat uterine tissue as well as cyclooxygenase-1 (COX-1) activity. MaterialsAndMethods Acute and chronic administration of estrogen (1 and 5 mg/ kg) progeste...

In a prospective, blind study, we have examined the relationship among the expression of human sperm surface progesterone receptors, the ability to undergo a mannose-stimulated acrosome reaction and the rate of fertilization in vitro. Individual aliquots of motile spermatozoa were surface-labelled with progesterone and/or mannose-fluoresceinated ligands. Spontaneous acrosome loss and the increa...

Breast cancers demonstrate a gradient of responsiveness to endocrine therapy according to hormone receptor status, with tumors positive for both estrogen and progesterone receptors responding most favorably. The authors hypothesized that reproductive risk factors, which are probably mediated by endogenous hormones, would also differ according to receptor status, and that tumors positive for bot...

Our goal was to examine the effect of deficiency of the lipoprotein receptor, scavenger receptor class B type I (SR-BI), on progesterone secretion in human granulosa cells (HGL5). Scrambled or SR-BI small interfering RNA [knockdown (KD)] cells were exposed to dimethylsulfoxide [DMSO, vehicle for forskolin (Fo)], Fo, serum, high-density lipoprotein, low-density lipoprotein (LDL), or Fo plus lipo...

The metabolism of progesterone bound to uterine nuclear progesterone receptors was accelerated in vitro by incubation at 25°C for 30min with NADPH generator. The characteristics of progesterone metabolites and receptors were examined by 3H-R5020 exchange assay. Progesterone bound nuclei were prepared from uteri of estradiol-primed progesteronetreated ovariectomized rats. The specific nuclear R5...

Feminization in men occurs when the effective ratio of androgen to estrogen is lowered. Since sufficient estrogen is produced in normal men to induce breast enlargement in the absence of adequate amounts of circulating androgens, it has been generally assumed that androgens exert an antiestrogenic action to prevent feminization in normal men. We examined the mechanisms of this effect of androge...

Although it is well known that progesterone alters uterine contractility and plays an important role in maintenance of pregnancy, the biochemical mechanisms by which progesterone alters uterine contractility in human gestation are less clear. In this investigation we sought to identify progesterone-induced adaptations in human myometrial smooth muscle cells that may alter Ca2+signaling in respo...

OBJECTIVE The expression of oestrogen and progesterone receptors in patients with adenocarcinoma of the uterine cervix was examined in order to determine their influence on prognosis and to evaluate the association between the steroid receptor expression and various clinicopathologic parameters. PATIENTS AND METHODS Oestrogen and progesterone receptor expression was investigated by immunohist...

Recent studies have demonstrated that physiological doses of progesterone may facilitate the androgen-dependent display of male sexual behavior in laboratory rats and three species of lizard. We used mice with a targeted disruption of the progesterone receptor to investigate whether such interactions exist in male mice and whether they may be modified by sexual experience. We found that naive i...

Progesterone (P4), which is produced by the corpus luteum (CL), creates proper conditions for the embryo implantation, its development, and ensures proper conditions for the duration of pregnancy. Besides the non-genomic activity of P4 on target cells, its main physiological effect is caused through genomic action by the progesterone nuclear receptor (PGR). This nuclear progesterone receptor oc...