The Mechanism of 17β-Estradiol Uptake into Prolactin-Producing Rat Pituitary Cells (GH3 Cells) in Culture

摘要: Estrogens stimulate PRL synthesis in cultured GH3 cells, which are clonal strains derived from the rat pituitary gland. This model system was used to study mechanism by 17β-estradiol (E2) enters target cells. The cellular uptake of [3H]E2 rapid at 37 C and reached half-maximal values within 10–15 sec. Maximal observed less than 2 min C. initial rates E2 were a linear function extracellular hormone concentration. intact cells binding cytosol studied different temperatures resulted Arrhenius plots, energies activation 39.0 33.5 kJ mol−1 degree−1, respectively. Purified membrane fractions, showed specific sites for [3H]TRH, displayed same maximal absence or presence cold hormone. amount membraneassociated increased linearly with temperature effect on o...