Biomaterial Database

Direct inhibition of testicular steroidogenesis and gonadotrophin receptor levels by [(imBzl)-D-His6, Pro9-NEt]GnRH and [D-Trp6, Pro9-NEt]GnRH, potent agonists of GnRH. 1982

Y Q Cao, and K Sundaram, and C W Bardin, and J Rivier, and W Vale

The effects of [(imBzl)-D-His6, Pro9-NEt]GnRH and [D-Trp6, Pro9-NEt]GnRH on testicular function in rats was evaluated. In adult rats the administration of 0.01, 0.1 or 10 micrograms of either agonist induced rapid increases in serum LH, FSH and testosterone (T) levels which started to decline within several hours. Both agonists caused a decrease in testicular LH and FSH receptor concentrations. The testicular FSH receptor concentration started to decline earlier than the LH receptor concentration but, both reached their lowest levels by day 2 after the administration of the agonists. The recovery of FSH receptor content was slower than that of LH. The extrapituitary effects of the 2 agonists were investigated in immature hypophysectomized animals. Administration of hCG (5 IU daily) to hypophysectomized rats for 5 days caused an increase in serum T levels. Concomitant administration of either of the agonists (10 micrograms) inhibited the steroidogenic action of hCG. Administration of the agonists alone caused a reduction in testicular LH receptor concentration in hypophysectomized rats. Treatment of the hypophysectomized rats for 0-4 days suggested that the direct antitesticular action of the agonists requires 1-2 days to become evident.

UI	MeSH Term	Description	Entries
D007016	Hypophysectomy	Surgical removal or destruction of the hypophysis, or pituitary gland. (Dorland, 28th ed)	Hypophysectomies
D007986	Luteinizing Hormone	A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.	ICSH (Interstitial Cell Stimulating Hormone),Interstitial Cell-Stimulating Hormone,LH (Luteinizing Hormone),Lutropin,Luteoziman,Luteozyman,Hormone, Interstitial Cell-Stimulating,Hormone, Luteinizing,Interstitial Cell Stimulating Hormone
D007987	Gonadotropin-Releasing Hormone	A decapeptide that stimulates the synthesis and secretion of both pituitary gonadotropins, LUTEINIZING HORMONE and FOLLICLE STIMULATING HORMONE. GnRH is produced by neurons in the septum PREOPTIC AREA of the HYPOTHALAMUS and released into the pituitary portal blood, leading to stimulation of GONADOTROPHS in the ANTERIOR PITUITARY GLAND.	FSH-Releasing Hormone,GnRH,Gonadoliberin,Gonadorelin,LH-FSH Releasing Hormone,LHRH,Luliberin,Luteinizing Hormone-Releasing Hormone,Cystorelin,Dirigestran,Factrel,Gn-RH,Gonadorelin Acetate,Gonadorelin Hydrochloride,Kryptocur,LFRH,LH-RH,LH-Releasing Hormone,LHFSH Releasing Hormone,LHFSHRH,FSH Releasing Hormone,Gonadotropin Releasing Hormone,LH FSH Releasing Hormone,LH Releasing Hormone,Luteinizing Hormone Releasing Hormone,Releasing Hormone, LHFSH
D008297	Male		Males
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D011962	Receptors, FSH	Cell surface proteins that bind FOLLICLE STIMULATING HORMONE with high affinity and trigger intracellular changes influencing the behavior of cells.	FSH Receptors,Follicle-Stimulating Hormone Receptors,Receptors, Follicle-Stimulating Hormone,FSH Receptor,Follicle-Stimulating Hormone Receptor,Follicle Stimulating Hormone Receptor,Follicle Stimulating Hormone Receptors,Hormone Receptor, Follicle-Stimulating,Hormone Receptors, Follicle-Stimulating,Receptor, FSH,Receptor, Follicle-Stimulating Hormone,Receptors, Follicle Stimulating Hormone
D011974	Receptors, LH	Those protein complexes or molecular sites on the surfaces and cytoplasm of gonadal cells that bind luteinizing or chorionic gonadotropic hormones and thereby cause the gonadal cells to synthesize and secrete sex steroids. The hormone-receptor complex is internalized from the plasma membrane and initiates steroid synthesis.	Chorionic Gonadotropin Receptors,Human Chorionic Gonadotropin Receptors,ICSH Receptors,LH Receptors,LH-hCG Receptor,LH-hCG Receptors,Luteinizing Hormone Receptors,Lutropin Receptor,Lutropin Receptors,Receptors, Chorionic Gonadotropin,Receptors, Human Chorionic Gonadotropin,Receptors, Interstitial Cell-Stimulating Hormone,Receptors, Luteinizing Hormone,hCG Receptors,Chorionic Gonadotropin Receptor,Human Chorionic Gonadotropin Receptor,LH Receptor,Luteinizing Hormone Receptor,Receptors, ICSH,Receptors, Interstitial Cell Stimulating Hormone,Receptors, LH-hCG,Receptors, Lutropin,Receptors, hCG,hCG Receptor,Gonadotropin Receptor, Chorionic,Gonadotropin Receptors, Chorionic,Hormone Receptor, Luteinizing,Hormone Receptors, Luteinizing,LH hCG Receptor,LH hCG Receptors,Receptor, Chorionic Gonadotropin,Receptor, LH,Receptor, LH-hCG,Receptor, Luteinizing Hormone,Receptor, Lutropin,Receptor, hCG,Receptors, LH hCG
D005640	Follicle Stimulating Hormone	A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.	FSH (Follicle Stimulating Hormone),Follicle-Stimulating Hormone,Follitropin
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia