We previously isolated a novel dodecapeptide containing a C-terminal -Arg-Phe-NH(2) sequence, SIKPSAYLPLRF-NH(2) (RFamide peptide), from the Japanese quail (Coturnix japonica) brain. This novel quail peptide was shown to be located in neurons of the paraventricular nucleus (PVN) and their terminals in the median eminence (ME), and to decrease gonadotropin release from cultured anterior pituitar...

The precise interplay of hormonal influences that governs gonadotropin hormone production by the pituitary includes endocrine, paracrine and autocrine actions of hypothalamic gonadotropin-releasing hormone (GnRH), activin and steroids. However, most studies of hormonal regulation of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in the pituitary gonadotrope have been limited to...

The gonadal receptor for luteinizing hormone LH and chorionic gonadotropin was extracted in soluble form from a particulate binding fraction of the interstitial cells of the rat testis by treatment with the nonionic detergent Triton X-100. During binding studies with the soluble receptor and 12ZI-labeled human chorionic gonadotropin (hCG), receptor-bound and free forms of the hormone were separ...

Our objective was to study the direct action of a GnRH-I agonist, leuprolide acetate (LA), on ovarian steroidogenesis in preovulatory follicles obtained from equine chorionic gonadotropin (eCG)-treated rats. Previously, we have demonstrated an inhibitory effect of LA on steroidogenesis and follicular development. In this study, we tested the hypothesis that gonadotropin-releasing hormone (GnRH)...

Binding of human [(125)I]luteinizing hormone to homogenates of luteinized rat ovaries is dependent upon time, temperature, and pH and is saturable. Injection of human chorionic gonadotropin in vivo or addition of unlabeled human chorionic gonadotropin or human or ovine luteinizing hormone in vitro inhibits binding, whereas follicle stimulating hormone or prolactin is without effect. The dissoci...

Abstract Background Hypogonadotropic hypogonadism (HH) is a rare condition in which there gonadal hypofunction due to absence of gonadotropin drive. In this condition, are very low serum levels gonadotropins. Pituitary gland may itself have some disease or disorder, be loss gonadotropin-releasing hormone (GnRH) pulses from the hypothalamus. The pharmacological interventions HH women formed basi...

Objective Opioid consumption has been widely increasing across the globe; however, it can cause adverse effects on the body. Morphine, an opioid, can reduce sex hormones and fertility. Withania somnifera (WS) is a traditional herb used to improve sexual activities. This study strives to investigate the effect of WS on sex hormones and gonadotropins in addicted male rats. MaterialsAndMethods In ...