SEMINAL-VESICLES ARE NOVEL SITES OF LUTEINIZING-HORMONE HUMAN CHORIONIC GONADOTROPIN-RECEPTOR GENE-EXPRESSION

The hypothesis that rat seminal vesicles may contain luteinizing hormo ne (LH)/human chorionic gonadotropin (hCG) receptors was tested by mea ns of a number of different techniques. Northern blotting demonstrated that rat seminal vesicles contained multiple LH/hCG-receptor transcri pts. in situ hybridization revealed that these transcripts were presen t primarily in the principal epithelial cells lining the lumen. Wester n immunoblotting detected proteins, two of which disappeared (80 and 4 6 kDa) and another of which decreased (30 kDa) after preabsorption of the receptor antibody with excess receptor peptide. Ligand blotting sh owed that I-125-hCG could bind only to an 80-kDa protein and that this binding was inhibited by coincubation with excess unlabeled hCG. Immu nocytochemistry demonstrated that LH/hCG-receptor protein was present primarily in the principal epithelial cells. In conclusion, our data d emonstrate that seminal vesicles contain LH/hCG receptors, thus making this previously unsuspected male accessory reproductive organ a poten tial target of direct regulation by LH.