Adult and immature male rats were hypophysectomized and injected daily with saline or 0.2 or 2 μg of superactive Luteinizing Hormone Releasing Hormone (LHRH) agonist, [D-Trp6]-LHRH subcutaneously for seven days - with, or without, concomitant treatment of 1 IU Human Chorionic Gonadotropin (hCG) or 50 IU Pregnant Mare Serum. The administration of [D-Trp6]-LHRH reduced Luteinizing Hormone/Human Chorionic Gonadotropin receptors in all cases. The magnitude of this reduction was dose-related. As small a dose as 0.2 μg of the peptide resulted in approximately a 72% reduction of the receptors. The results suggest a direct action of [D-Trp6]-LHRH on the testis. It also indicated that reduction of testicular Luteinizing Hormone/Human Chorionic Gonadotropin receptors by the peptide is not necessarily due to the over-stimulation of Luteinizing Hormone (LH) release from the pituitary through a "down regulation" mechanism.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and biophysical research communications|
|State||Published - Oct 12 1979|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology