Estradiol binding to cell surface raises cytosolic free calcium in T cells.
The Fura-2 method is used to examine a possible action of 17beta-estradiol (E2) on [Ca2+]i of splenic T cells isolated from female C57BL/10 mice. E2 concentrations between 10 fM and 10 nM induce a rapid and dose-dependent increase in [Ca2+]i due to Ca2+ influx and release of Ca2+ from intracellular stores. Ca2+ influx is mediated by Ca2+ channels which are completely blockable by Ni2+ and partly by nifedipine. The antiestrogen tamoxifen does not inhibit the E2-induced rise in [Ca2+]i. Ca2+ influx and Ca2+ release from intracellular stores is also inducible by plasma membrane impermeable E2 conjugated to BSA. E2-BSA-FITC binds to the surface of T cells of both the CD4+ and CD8+ subset. Our data suggest a novel E2-signalling pathway in T cells which is not mediated through the classical nuclear estrogen receptor response but rather through putative plasma membrane receptors for E2.
Benten
W P
WP
Division of Molecular Parasitology and Center for Biological and Medical Research, Heinrich-Heine-University, Düsseldorf, Germany.
Lieberherr
M
M
Giese
G
G
Wunderlich
F
F
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism*; D004965:Estrogen Antagonists / Q000494:pharmacology; D005260:Female; D066298:In Vitro Techniques; D051379:Mice; D008810:Mice, Inbred C57BL; D011485:Protein Binding; D011959:Receptors, Estradiol / Q000378:metabolism*; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D013629:Tamoxifen / Q000494:pharmacology
D004965:Estrogen Antagonists; D011959:Receptors, Estradiol; D013629:Tamoxifen; D004958:Estradiol; D002118:Calcium