G protein-coupled estrogen receptor (GPER), or GPR30, specifically binds natural and man-made estrogens. It is thought to be involved in estrogen-sensitive cancers. GPER knockout mice are fertile, although they exhibit thymic atrophy, impaired glucose tolerance, and altered bone growth. G-15 is a cell-permeable non-steroidal antagonist of GPER (Ki = 20 nM). It displays low affinity cross-reactivity with the classical estrogen receptor (ER), ERα, so that at doses greater than 1 μM it is capable of mediating limited ER-dependent transcriptional activity. G-15 antagonizes the anti-depressive effects of estrogen in vivo.
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