Characteristics of the delayed rectifier K+ current in guinea pig hypertrophied ventricular myocytes induced by thyroxine
- VernacularTitle:甲状腺素诱导的豚鼠肥厚心肌中延迟整流钾电流离子通道特征
- Author:
Guangqin ZHANG
;
Xuemei HAO
;
Yuping MA
;
Peiai ZHOU
;
Caihong WU
;
Dezai DAI
- Publication Type:Journal Article
- From:
Chinese Pharmacological Bulletin
2001;17(2):174-177
- CountryChina
- Language:Chinese
-
Abstract:
AIM To study the characteristic of th e rapidly activating component (Ikr) and the slowly activating compone nt (Iks) of the delayed rectifier K+ current in guinea pig hypertrop hi ed ventricular myocytes induced by thyroxine. METHOD The whole c ell patch clamp techniques were used. RESULTS In hypertrophied ve ntricular myocytes, the magnitude of IKr and IKs were great ly augmented with more positive depolarizations, and the degree of increase of IKr tail and IKs were greater than that of IKr an d IKs tail, respectively. By measuring the amplitude of tail currents which reflected the degree of activation, the activation curve of IKs was shifted toward more negative potential, but that of IKr was marked ly unaffected in hypertrophied myocytes. CONCLUSION Hypertrophied ventricular myocytes induced by thyroxine obviously increased IKr and IKs.
