Ethinylestradiol treatment induces multiple canalicular membrane transport alterations in rat liver.

摘要: We investigated the effects of 17 alpha-ethinylestradiol treatment rats on various transport functions in isolated basolateral and canalicular liver plasma membrane vesicles. Both subfractions were purified to a similar degree from control cholestatic livers. Although moderate lipid alterations predominantly observed vesicles, no change Na+/K(+)-ATPase activity was found. Furthermore, while Na(+)-dependent taurocholate uptake decreased by approximately 40% maximal velocity ATP-dependent 63% membranes. In contrast, only minimal changes or at all for electrogenic "cholestatic" membranes total microsomes, respectively. However, vesicles livers also exhibited marked reductions S-(2,4-dinitrophenyl)glutathione adenosine, same HCO3-/SO4- exchange Na+/glycine cotransport activities markedly stimulated. These data show that addition previously demonstrated sinusoidal abnormalities ethinylestradiol-induced cholestasis is associated with multiple rat liver. Hence, functional both polar surface domains might ultimately be responsible inhibitory estrogens organic anion excretory capacity bile formation