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A receptor-independent effect of estrone sulfate on the HERG channel
Shoko Kakusaka1, Mahoko Asayama, Asami Kaihara
1Department of Bio-Informational Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan.
Abstract:
We recently reported that physiological concentrations of 17beta-estradiol partially down-regulate cardiac rapidly-activating delayed rectifier K(+) currents (hERG currents) independently of estrogen-receptor signaling. To determine if other estrogens have the same effect as that of 17beta-estradiol, we investigated receptor-independent effects of estrone, estrone 3-sulfate, and estriol on hERG currents in patch-clamped estrogen-negative HEK293 cells. Only estrone 3-sulfate partially suppressed hERG currents in a receptor-independent manner by modifying the gating. The concentration-dependence of estrone 3-sulfate revealed that physiological levels of circulating estrone 3-sulfate can modulate hERG currents to the maximal extent in both women and men at any age.
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