Gonadotropin-releasing hormone (GnRH) is the primary regulator of mammalian reproductive function in both males and females. It acts via G-protein coupled receptors on gonadotropes to stimulate synthesis and secretion of the gonadotropin hormones luteinizing hormone and follicle-stimulating hormone. These receptors couple primarily via G-proteins of the Gq/ll family, driving activation of phosp...

Nesfatin-1 is an anorexigen in goldfish. In the present study, we provide novel data indicating the presence and regulatory effects of nesfatin-1 on the hypothalamo-pituitary-ovarian (HPO) axis of goldfish. Nucleobindin-2 (NUCB2)/nesfatin-1-like immunoreactive (ir) cells are present in the hypothalamus and in the pituitary, suggesting a hypophysiotropic role for nesfatin-1. NUCB2/nesfatin-1-lik...

The physical properties of detergent-solubilized gonadotropin receptor-hormone complexes, determined by density gradient centrifugation and gel filtration, were compared after in vivo and in vitro labeling of specific ovarian binding sites with radioiodinated human chorionic gonadotropin (hCG). Following intravenous administration of biologically active 125I-labeled hCG, up to 50% of the gonado...

The function of the central aspects of the hypothalamic-pituitary-gonadal axis has been assessed in a number of ways including direct measurements of the hypothalamic output and indirect measures using gonadotropin release from the pituitary as a bioassay for reproductive neuroendocrine activity. Here, methods for monitoring these various parameters are briefly reviewed and then examples presen...

The temporal relationship between redistribution of receptors to lutropin (luteinizing hormone)/human chorionic gonadotropin in cultured rat ovarian granulosa cells and the cellular response to hormonal challenge were studied. Visualization of receptor-bound human chorionic gonadotropin by indirect immunofluorescence, with hormone-specific antibodies after fixation with 2% formaldehyde, reveale...

An isolated deficiency of pituitary gonadotropins was demonstrated in six 46 XY males, 22 to 36 years of age, with and without anosmia. Undetectable or low levels of serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) clearly separated hypogonadotropic from normal adult males. Chronic (8-12 wk) administration of clomiphene citrate caused no increase in serum FSH or LH in gonad...

Chub mackerel, Scomber japonicus, is heavily farmed and harvested due to its demand as a high-quality protein source rich in fatty acids. However, the effects of environmental cues on sexual maturation fish remain understudied. We aim elucidate effect light manipulation hormones related reproduction stress response species. Mackerel were exposed different photoperiods (12 h light:12 dark or 14 ...

To evaluate gonadotropin release in polycystic ovary syndrome (PCO), one or more of the following hypothalamic-pituitary function tests were performed on 24 patients with the syndrome. These tests included (a) the pulsatile pattern and day-to-day fluctuation of gonadotropin release; (b) effects of exogenous estrogen and antiestrogen (clomiphene) administration on gonadotropin release; and (c) p...

Background: The long protocol has been recognized as the gold standard in controlled ovarian hyperstimulation (COH). However, full dose of gonadotropin-releasing hormone agonist (GnRH-a) under prolonged become increasingly popular China. This study sought to compare pregnancy outcomes among following 3 groups: a group, and 2 types improved groups.