By using a yeast two-hybrid screen we identified GIPC (GAIP-interacting protein C terminus), a protein with a type I PDZ domain as a novel human lutropin receptor (hLHR) binding partner. Pull-down and immunoprecipitation assays confirmed this interaction and showed that it is dependent on the PDZ domain of GIPC and the C-terminal tetrapeptide of the hLHR. To characterize the functional conseque...

A new technique in which polyethylene glycol is added to double-antibody assays of lutropin and follitropin eliminates the need for an incubation period during the separatory phase. After the antigen-first-antibody equilibrium reaction, the second antibody and polyethylene glycol (30 g/L final dilution) are added, the tubes are immediately centrifuged, each supernate is aspirated, and the preci...

We evaluated the analytical performance and clinical utility of three dual-label simultaneous assays for lutropin and follitropin by comparison with widely used individual assays for these analytes (Diagnostic Products Corp.; DPC). Of the three assays evaluated, "Cotropin" (Clinetics Corp.) and "Combostat" (Micromedics Systems, Inc.) compared favorably with the DPC assay with respect to recover...

Luteinizing hormone-releasing hormone (LHRH) neurons and fibers are located in the anteroventral hypothalamus, specifically in the preoptic medial area and the organum vasculosum of the lamina terminalis. Most luteinizing hormone-releasing hormone neurons project to the median eminence where they are secreted in the pituitary portal system in order to control the release of gonadotropin. The ai...

Two regions of human thyrotropin (thyroid-stimulating hormone, TSH) receptor (TSHR) (residues 12-44 and 308-364) were selected on the basis that they exhibit no sequence resemblance to luteinizing hormone/chorionic gonadotropin receptor. Five synthetic overlapping peptides (12-30, 24-44, 308-328, 324-344, and 339-364) were studied for their ability to bind 125I-labeled human TSH (hTSH), its iso...

Six hundred milligrams of follicle-stimulating hormone (FSH), containing 110 NIH-FSH-S1 units/mg, was isolated from 9 kg of equine pituitary glands. The equine FSH was dissociated into alpha- and beta-subunits. A tentative amino acid sequence of the alpha-subunit was determined. The alpha-subunit contained 82 amino acids. The equine FSH-alpha is shorter by 10 to 14 amino acids at the NH2 termin...