Biomaterial Database

Changes in available gonadotropin receptors in the corpus luteum of the rhesus monkey during simulated early pregnancy. 1984

J S Ottobre, and A C Ottobre, and R L Stouffer

Stimulation of the primate corpus luteum (CL) by endogenous CG in early pregnancy or by exogenous human CG (hCG) in simulated early pregnancy, is transient, despite continued exposure to rising concentrations of CG. The objective of this study was to determine if the transitory response of the CL to CG is related to changes in gonadotropin receptors. Numbers and affinities of available LH/CG binding sites were characterized in the CL of rhesus monkeys (n = 27) during prolonged CG exposure in simulated early pregnancy, and the temporal relationship between changes in receptor parameters and in luteal function was examined. Administration of hCG increased progesterone concentrations above pretreatment levels within 9 h (2.2 +/- 0.8 vs. 7.6 +/- 1.1 ng/ml, mean +/- SE, P less than 0.05); the relative increase (345% of control) in serum progesterone was more profound than that of available hCG binding sites (135%, P greater than 0.05) or luteal weight (128%, P greater than 0.05) over this interval. Receptor affinities for hCG remained comparable to pretreatment values (Kd = 1.1 +/- 0.2 X 10(-10) M) throughout this 9-h period. A significant diminution in available hCG receptors occurred between 9 h (12.7 +/- 2.1 fmol/mg tissue) and 3 days (7.4 +/- 1.5 fmol/mg tissue) of hCG treatment (P less than 0.05). The loss of available CG receptors preceded a significant decline in serum progesterone concentrations. Serum progesterone decreased by 6 days (4.0 +/- 0.6 ng/ml, P less than 0.05) of hCG treatment, as did receptor affinity for hCG (Kd = 4.7 +/- 0.9 X 10(-10) M, P less than 0.05). Numbers and affinities of available receptors for hCG and serum progesterone concentrations fell before any decrease in luteal weight. Binding capacities and receptor affinities for human LH were comparable to those for hCG throughout simulated early pregnancy. In conclusion, the population of available LH/CG receptors in the macaque CL is maintained, or perhaps modestly increased, amidst dramatic stimulation of luteal function during early CG exposure. The subsequent diminution of number and affinity of available LH/CG receptors during prolonged exposure to CG in early pregnancy may compromise CL function and thus participate in the establishment of the transient nature of the luteal response to CG.

UI	MeSH Term	Description	Entries
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
D008253	Macaca mulatta	A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.	Chinese Rhesus Macaques,Macaca mulatta lasiota,Monkey, Rhesus,Rhesus Monkey,Rhesus Macaque,Chinese Rhesus Macaque,Macaca mulatta lasiotas,Macaque, Rhesus,Rhesus Macaque, Chinese,Rhesus Macaques,Rhesus Macaques, Chinese,Rhesus Monkeys
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011270	Pregnancy, Animal	The process of bearing developing young (EMBRYOS or FETUSES) in utero in non-human mammals, beginning from FERTILIZATION to BIRTH.	Animal Pregnancies,Animal Pregnancy,Pregnancies, Animal
D011374	Progesterone	The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.	Pregnenedione,Progesterone, (13 alpha,17 alpha)-(+-)-Isomer,Progesterone, (17 alpha)-Isomer,Progesterone, (9 beta,10 alpha)-Isomer
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
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
D003338	Corpus Luteum	The yellow body derived from the ruptured OVARIAN FOLLICLE after OVULATION. The process of corpus luteum formation, LUTEINIZATION, is regulated by LUTEINIZING HORMONE.	Corpora Lutea,Lutea, Corpora
D005260	Female		Females
D006063	Chorionic Gonadotropin	A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).	Chorionic Gonadotropin, Human,HCG (Human Chorionic Gonadotropin),Biogonadil,Choriogonadotropin,Choriogonin,Chorulon,Gonabion,Human Chorionic Gonadotropin,Pregnyl,Gonadotropin, Chorionic,Gonadotropin, Human Chorionic