The effects of various substrates on the binding of agonists to muscarinic receptors were studied in the rat hypothalamus and adenohypophysis by competition experiments using the highly specific tritiated muscarinic antagonist N-methyl-4-piperidyl benzilate. It was found that agonist binding properties were affected only by the steroid sex hormones (beta-estradiol and progesterone), both of whi...

Plasma membranes isolated from bovine corpora lutea showed specific binding with 1251-human chorionic gonadotropin and 1251-human luteinizing hormone; unlabeled hormones competitively inhibited the binding. The binding of the 1251-human chorionic gonadotropin to the receptor was a saturable phenomenon and the half-saturation was attained at a concentration of 4 X lo-r0 M. Maximum hormone recept...

There is a strong association between nutrition and reproduction. Chronic dietary energy deficits as well as energy surpluses can impair reproductive capacity. Metabolic status impacts reproductive function at systemic level, modulating the hypothalamic GnRH neuronal network and/or the pituitary gonadotropin secretion through several hormones and neuropeptides, and at the ovarian level, acting ...

In glycoprotein hormone receptors, a subfamily of rhodopsin-like G protein-coupled receptors, the recognition and activation steps are carried out by separate domains of the proteins. Specificity of recognition of the hormones thyrotropin (TSH), lutropin (LH), human chorionic gonadotropin (hCG) and follitropin (FSH) involves leucine-rich repeats (LRRs) present in an N-terminal ectodomain, and c...

Effect of melatonin, testosterone and of both hormones given in parallel on rat epididymis was tested in rats given a single dose of 1 mg stilbestrol on the first day of the life. The hormones were given daily for 39 days, beginning from the 20th or 28th day of life. The single dose of estrogen treatment resulted in epididymis atrophy, accompanied by changes in glandular epithelium and in its s...

Human chorionic gonadotropin (hCG) belongs to thc family of cystine knot growth factors secreted by the placenta very early during pregnancy. Owing to the complexity of i ts structure and by virtue of being a heterodimer, it has proven to be an excellent model system for the study of prote in folding and protein-protein interaction. Several groups including us have carried out structure functio...

This review briefly highlights previous studies on the gonadotropin-releasing hormone (GnRH) and its approaches to improving fish reproduction in aquaculture industry. Reproductive system dysfunction of captive is main problem that has be treated depending compatibility species. caused by non-synchronized maturation female male broodstock, low quality broodstock. As shown studies, induced breed...

The ovary is itself a hormone secreting organ, and it has been shown that some ovarian tumors also secrete hormones. Granulosa cell tumors and theca cell tumors are hormone secreting tumors. There have been many reports on the histogeneses, character, and nomenclatures of these tumors. In 1944, Biskind et al. reported the development of granulosa cell tumors and luteoma by intrasplenic ovarian ...

The key function of reproduction is to propagate inheritable characteristics to new generations. The human female reproductive system consists of the hypothalamic– pituitary–ovarian axis and end organs such as the uterus and fallopian tubes. The endocrine axis involves both peptide hormones (gonadotropin-releasing hormone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH)) and ste...

The insect adipokinetic hormones (AKHs) are a large family of peptide hormones that are involved in the mobilization of sugar and lipids from the insect fat body during energy-requiring activities such as flight and locomotion, but that also contribute to hemolymph sugar homeostasis. Here, we have identified the first insect AKH receptors, namely those from the fruitfly Drosophila melanogaster ...