摘要
目的 研究雌激素对豚鼠心室肌细胞的非基因组作用。方法 方法采用全细胞膜片钳技术。结果17β-雌二醇1μmol/L和3μmol/L在1～2 min内快速抑制INa峰值,抑制率分别13.25％±4.71％,32.46%±4.82％。1μmol/L 17β-雌二醇亦可影响INa的电流-电压(Ⅰ-Ⅴ)曲线,使INa电流密度值在-30mV～+30 mV膜电位下显著降低。在-20 mV处,INa电流密度值由-120,48±7.05 pA/pF降至-101.91±11.00 pA/pF(P<0.01)。在+30 mV处,INa电流密度值由-39.55±10.50pA/pF降至-29.88±6.21pA/pF(P<0.05)。17β-雌二醇的抑制效应被DNA转录抑制剂-放线菌素D所阻断。且抑制效应与豚鼠的性别无关。结论 雌激素通过推测的非基因组效应快速抑制豚鼠心室肌细胞钠电流(INa),且该效应不被放线菌素D所阻断。
Objective The aim of this study was to investigate the nongenomic effect of estrogen in guinea-pig ventricular myocytes. Methods The whole-cell patch-clamp recording technique was used. Results 17β-estradiol 1μmol/L and 3 μMmol/L could, within 1-2 min, rapidly decreased the peak amplitude of INa by 13.25%±4.71% , (n=7, P<0. 01) , 32.46%±4.82% (n=6, P <0. 01) respectively. Current-Voltage curve of sodium current was shifted to upside by 1 μmol/L 17β-estradiol. The maximal inhibitory effect of 1 μmol/L 17β-estradiol on INa appeared near -20 mV, and the INa density was decreased from - 120. 48 ±7. 05 pA/pF to - 101. 91 ± 11.00pA/pF (P<0. 01). At +30 mV, a significant difference still existed in INa density between control ( -39. 55 ±10. 50pA/pF) and 17β-estradiol (-29.88±6.21 pA/pF) (P<0. 05). The inhibitory effect of 17β-estradiol on INa density was not blocked by pretreatment with actinomycin D, an inhibitor of DNA transcription (n=12,P>0. 05). There was no difference in the rapid inhibitory effect of 17βb-estradiol on INa between male and female guinea-pigs (n=12, P > 0. 05). Conclusion Estrogen could rapidly suppress guinea-pig ventricular myocytes INa by a putative nongenomic mechanism, which was not interrupted by actinomycin D.
出处
《医学分子生物学杂志》
CAS
CSCD
2004年第3期152-157,共6页
Journal of Medical Molecular Biology
基金
This work was supported by a grant from the National Nature Science Foundation of China(No.30271505).
