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[Effects of sex hormones on HERG potassium channels expressed in Xenopus oocytes].
Fiziol Zh. 2001; 47(2):24-31.FZ

Abstract

The repolarisation phase of cardiac action potential is characterized by sexual dimorphism suggesting the role of sex steroid hormones in the regulation of K+ channels. Here we report on the effects of testosterone and 17 beta-estradiol on HERG-encoded K+ channels, expressed in Xenopus oocytes. At 1M concentration testosterone decreased the amplitude of HERG-directed IKr (rapid component of cardiac delayed rectifier K+ current) by 30% within 30 min of exposure, while 17-estradiol had no effect. Testosterone did not alter the HERG channels kinetics, voltage-dependence, steady-state activation and inactivation properties suggesting that its action most probably involves the decrease of channels open probability and/or the level of their expression. The signaling pathways mediating testosterone-induced down-regulation of HERG channels in Xenopus oocytes remains to be elucidated. The effect of testosterone on HERG channels in Xenopus oocytes is opposite to what one might expect from shorter cardiac action potential duration and electrocardiographic QT-interval in males compared to females.

Authors+Show Affiliations

A. A. Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine.No affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

English Abstract
Journal Article

Language

ukr

PubMed ID

11392110

Citation

Osypenko, V M., et al. "[Effects of Sex Hormones On HERG Potassium Channels Expressed in Xenopus Oocytes]." Fiziolohichnyi Zhurnal (Kiev, Ukraine : 1994), vol. 47, no. 2, 2001, pp. 24-31.
Osypenko VM, Dehtiar VIe, Naĭd'onov VH, et al. [Effects of sex hormones on HERG potassium channels expressed in Xenopus oocytes]. Fiziol Zh. 2001;47(2):24-31.
Osypenko, V. M., Dehtiar, V. I. e., Naĭd'onov, V. H., & Shuba, I. a. M. (2001). [Effects of sex hormones on HERG potassium channels expressed in Xenopus oocytes]. Fiziolohichnyi Zhurnal (Kiev, Ukraine : 1994), 47(2), 24-31.
Osypenko VM, et al. [Effects of Sex Hormones On HERG Potassium Channels Expressed in Xenopus Oocytes]. Fiziol Zh. 2001;47(2):24-31. PubMed PMID: 11392110.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - [Effects of sex hormones on HERG potassium channels expressed in Xenopus oocytes]. AU - Osypenko,V M, AU - Dehtiar,V Ie, AU - Naĭd'onov,V H, AU - Shuba,Ia M, PY - 2001/6/8/pubmed PY - 2002/7/12/medline PY - 2001/6/8/entrez SP - 24 EP - 31 JF - Fiziolohichnyi zhurnal (Kiev, Ukraine : 1994) JO - Fiziol Zh VL - 47 IS - 2 N2 - The repolarisation phase of cardiac action potential is characterized by sexual dimorphism suggesting the role of sex steroid hormones in the regulation of K+ channels. Here we report on the effects of testosterone and 17 beta-estradiol on HERG-encoded K+ channels, expressed in Xenopus oocytes. At 1M concentration testosterone decreased the amplitude of HERG-directed IKr (rapid component of cardiac delayed rectifier K+ current) by 30% within 30 min of exposure, while 17-estradiol had no effect. Testosterone did not alter the HERG channels kinetics, voltage-dependence, steady-state activation and inactivation properties suggesting that its action most probably involves the decrease of channels open probability and/or the level of their expression. The signaling pathways mediating testosterone-induced down-regulation of HERG channels in Xenopus oocytes remains to be elucidated. The effect of testosterone on HERG channels in Xenopus oocytes is opposite to what one might expect from shorter cardiac action potential duration and electrocardiographic QT-interval in males compared to females. SN - 2522-9028 UR - https://www.unboundmedicine.com/medline/citation/11392110/[Effects_of_sex_hormones_on_HERG_potassium_channels_expressed_in_Xenopus_oocytes]_ DB - PRIME DP - Unbound Medicine ER -