Leutinizing hormone receptor

Pubertal gynecomastia is common, can be seen in 65% of the adolescent boys and is considered physiological. It is thought to be due to transient imbalance between the ratio of testosterone and estradiol in the early stages of puberty. It resolves in 1-2 years and requires no treatment. However, more persistent and severe pubertal gynecomastia is less common and can be associated with pathological disorders. These can be due to diminished androgen production, increased estrogen production or androgen resistance...

BACKGROUND: Insulin sensitizers like metformin and pioglitazone are clinically used since last decades for the treatment of PCOS, but their efficacy and possible role in PCOS patients remains questionable. Also, the mechanism by which these insulin sensitizers show effect is not clear. AIM OF THE STUDY: To evaluate the effect of metformin and pioglitazone on leutinizing hormone and follicle stimulating hormone receptor mRNA expression, hyperandrogenism and insulin resistance in high fat diet induced and letrozole induced PCOS in rats...

Polycystic ovary syndrome (PCOS) is associated with hyperandrogenism, oligo-anovulation, polycystic ovaries and metabolic syndrome. Many researchers reported that PCOS often starts with menarche in adolescents. Presently available animal model focuses on ovarian but not metabolic features of PCOS. Therefore, we hypothesized that high-fat diet feeding to pre-pubertal female rats results in both reproductive and metabolic features of PCOS. Pre-pubertal female rats were divided into two groups: group I received normal pellet diet and group II received high-fat diet (HFD)...

Polycystic ovary syndrome (PCOS) is one of the most common endocrine-metabolic disorders; however, its pathophysiology is still unclear. Certain polymorphisms of luteinizing hormone beta-subunit (LHβ) and LH/choriogonadotrophin receptor (LHCGR) genes may lead to changes in the bioactivity of this hormone. We aimed to investigate possible associations between polymorphisms in the LHβ and LHCGR genes and PCOS among Egyptian women. We also aimed to shed light on the impact of these polymorphisms on LH level, hormonal, and metabolic features of PCOS...

PURPOSE: Previous studies identified follicle-stimulating hormone receptor (FSHR) and luteinizing hormone/choriogonadotropin receptor (LHCGR) genes as polycystic ovary syndrome (PCOS) susceptibility loci, which was dependent on the racial/ethnic background of studied population. We investigated the association of genetic variants in FSHR and LHCGR with PCOS in Bahraini Arab women. METHODS: A retrospective case-control study, involving 203 women with PCOS, and 211 age- and ethnically-matched control women...

CONTEXT: Polycystic ovarian syndrome (PCOS) is considered to be the most common endocrine disorder affecting women. Melatonin, a small lipophilic indoleamine, and reproductive hormones may be interrelated. Melatonin influences sex steroid production at different stages of ovarian follicular maturation as melatonin receptors have been demonstrated at multiple sites in ovary and in intrafollicular fluid. It plays role as an antioxidant and free radical scavanger which protects follicles from oxidative stress, rescuing them from atresia, leading to complete follicular maturation and ovulation...

Although hyperandrogenism is an important condition and is considered the possible pathogenesis behind polycystic ovary syndrome (PCOS), data supporting this is still scarce. We sought to determine whether or not prenatal androgen exposure leads to PCOS and the possible cellular mechanisms involved. To induce prenatal androgen exposure, pregnant rats were treated with daily subcutaneous injections of free testosterone (T) or dihydrotestosterone (DHT) from embryonic days 16 to 19, and their female offspring were studied as adults...

BACKGROUND: The standard hormonal therapy with currently available antiandrogens and the leutinizing hormone releasing hormone (LHRH) analogs is not effective in the hormone-refractory stage of prostate cancer due to changes in androgen receptor (AR) signaling axis. In this refractory stage, AR continues to play a significant role in the growth of cancer cells even though the cancer cells are no longer dependent on the level of circulating androgens. METHODS: A series of 11beta-Delta(9)-19 nortestosterone compounds were designed through structure-based rationale and tested for their binding affinity against AR and glucocorticoid receptor (GR) using fluorescence polarization assays, their agonistic ability to induce AR dependent transcription using PSA-driven report gene assays, and their growth inhibitory affects against a series of AR positive (LAPC4, LNCap, and CWR22R) and negative human prostate cancer cell lines (PC3) using MTT cell proliferation assays...

We investigated the effect of daily intracerebroventricular (ICV) leptin administration (neonatal age 2-7 days) on hypothalamic neuropeptides (neuropeptide Y, alpha-melanocyte-stimulating hormone) that regulate food intake, body weight (BW) gain, and the metabolic/hormonal profile in suckling (8 and 21 days) and adult rat (35, 60, 90, and 120 days). ICV leptin (0.16 mug.g BW(-1).dose(-1); n = 70) led to a postnatal decline in BW (P = 0.0002) that persisted only in the adult females (P = 0.002). The postnatal decline in BW due to leptin was associated with a decline in food intake (P = 0...

Advances in immunocytochemistry, electron microscopy, cell culture, and molecular techniques have demonstrated that 80 to 90% of the clinically nonfunctioning pituitary adenomas are gonadotrope-derived and recently recognized as gonadotropinomas, which account for as many as 40 to 50% of all pituitary macroadenomas. Patients usually present with mass effects including visual field loss and headache, hypogonadism, and hypopituitarism. Commonly, the tumor is found incidentally. Recently, a few patients with gonadotropinomas were reported to have hormonal hypersecretion syndromes such as ovarian hyperstimulation, testicular enlargement, and precocious puberty...

Polycystic ovary syndrome (PCOS) is a disorder characterized by hyperandrogenism and chronic anovulation. Although the etiology of PCOS is unknown, perturbations of gonadotropin secretion are one of the hallmarks of this disorder. In normal menstrual physiology, the monotropic rise of plasma follicle-stimulating hormone (FSH) during the luteal-follicular transition is critical for follicular development and subsequent ovulation. One of the mechanisms by which FSH is differentially synthesized involves the luteal slowing of gonadotropin-releasing hormone (GnRH) pulse frequency by ovarian steroids...

Lamprey gonadotropin-releasing hormone-III (l-GnRH-III), the putative follicle-stimulating hormone (FSH)-releasing factor (FSHRF), exerts a preferential FSH-releasing activity in rats both in vitro and in vivo. To test the hypothesis that l-GnRH-III acts on its own receptors to stimulate gonadotropin release, the functional activity of this peptide at mammalian (m) leutinizing hormone (LH)RH receptors transfected to COS cells was tested. l-GnRH-III activated m-LHRH receptors only at a minimal effective concentration (MEC) of 10(-6) M, whereas m-LHRH was active at a MEC of 10(-9) M, at least 1,000 times less than that required for l-GnRH-III...

Scientific and commercial pharmacological interest in the role of galanin and galanin receptors in the regulation of food intake, energy balance, and obesity has waned recently, following initial enthusiasm during the 1980-1990s. It has been replaced by efforts to understand the role of newly discovered peptide systems such as the hypocretin/orexins, melanocortins and cocaine- and amphetamine-regulated transcript (CART) and their relationship to the important hormones, leptin and insulin. Thus, while numerous studies have revealed the ability of galanin to stimulate food intake via actions at sites within the hypothalamus, and shown reliable changes in hypothalamic galanin synthesis in response to food ingestion; findings including the lack of a 'body weight/obesity' phenotype in galanin transgenic mouse strains and a lack of agonists/antagonists for galanin receptor subtypes have probably served to reduce enthusiasm...

We report an 11-year-old boy with undermasculinized genitalia and an abnormally expanded CAG repeat length at exon 1 of the androgen receptor (AR) gene. He had microphallus and scrotal hypospadias with chordee, and underwent urethroplasty at 4 years of age. At 11 years of age, a gonadotropin releasing hormone (GnRH) test yielded a relatively high leutinizing hormone (LH) response (0.7-->20.4 IU/l) and a relatively low follicle-stimulating hormone (FSH) response (1.7-->4.8 IU/l), and an human chorionic gonadotropin (hCG) test showed sufficient responses of testosterone (0...

PROBLEM: Although leukocytes do not possess significant numbers of ovarian steroid hormone receptors, their numbers in the endometrium vary consistently, relative to the menstrual cycle. The possibility that cell types within the endometrium express leukocyte-attracting genes in response to ovarian hormones was investigated. METHOD OF STUDY: Endometrial biopsies were collected 10 days post-leutinizing hormone surge; the cell types were separated and cultured individually for 5 days in the presence of increasing amounts of estrogen or progesterone...

Because of the characteristic presentation of primary mediastinal large cell lymphoma (PMLCL) in young females its known origin from thymic B-cells, there might be a role in lymphomagenesis for estrogen receptors as well as for known neuroendocrine thymic mediators. A retrospective review of all patients with diffuse large cell lymphoma seen at our institution from January 1985 to January 1994 revealed 75 consecutive cases with a diagnosis of PMLCL. Through retrieval from our pathologic archives and requests to outside pathologists, we recovered and analyzed 17 biopsy specimens for the presence of the following hormone receptors: estrogen, beta endorphin, prolactin, T3, growth hormone, and leutinizing hormone...

PURPOSE: To define sequence motifs that can be used to identify peptide ligands of the melanocortin receptor (MCR). METHODS: Screening of combinatorial libraries has led to identification of D-Trp-Nle-NH2 (Nle, norleucine) and D-Trp-Arg-NH2 as the smallest structures known to antagonize the amphibian MCR (1). As the basis of a search paradigm, peptide-ligands containing these or similar motifs within their larger primary structure were examined for ability to antagonize amphibian and recombinant human MCRs...

Residues Phe33 and Arg35, individually, and a composite mutation of residues Arg42, Ser43, and Lys44 were changed to alanine in the human glycoprotein hormone common alpha-subunit using site-directed mutagenesis. These specific residues are highly conserved across species and have by chemical modification and synthetic peptide approaches been implicated in the binding of human chorionic gonadotropin (hCG) to leutinizing hormone (LH) receptor. In the present study we tested the hypothesis that specific alpha-subunit amino acid residues which stabilize the hormone receptor interaction for hCG have the same function in human follicle-stimulating hormone (hFSH)...

It is well established that gonadal steroids play an important role in the regulation of immune response. These substances exert their effect through estradiol and possibly dihydrotestosterone receptors located in the thymic reticuloepithelial cell matrix. In vivo treatment of male rats with estradiol has been shown to depress the cell mediated immune response as mediated through thymic serum factors. Castration stimulates the cell mediated immune response while thymectomy inhibits this effect. It also appears that growth hormone at physiological concentrations can directly inhibit thymocyte blast transformation in vitro while leutinizing hormone, follicle stimulating hormone, and prolactin do not directly affect thymocyte function...