【摘要】 目的 研究17β-雌二醇对Kv2.1钾电流和原代培养大鼠海马神经元延迟整流钾电流的作用。方法 采用HEK293-Kv2.1细胞培养、大鼠海马神经元原代培养和膜片钳全细胞记录技术。结果 17β-雌二醇浓度依赖地抑制Kv2.1钾电流和原代培养大鼠海马神经元延迟整流钾电流(Ik)。17β-雌二醇抑制Kv2.1钾电流和原代培养大鼠海马神经元延迟整流钾电流的IC50分别为2.4和4.0μmol·L-1。通道动力学研究发现,17β-雌二醇(3μmool·L-1)显著左移Kv2.1钾电流的稳态激活和失活曲线,但只显著左移海马神经元延迟整流钾电流稳态激活曲线,而不影响该电流的稳态失活曲线。结论 17β-雌二醇抑制Kv2.1钾电流与抑制Ik的程度相近,17β-雌二醇抑制Ik的作用可能部分通过阻断Kv2.1钾电流而实现。更多还原

【Abstract】 Aim To study the effects of 17β-estradiol on Kv2. 1 potassium channel current and delayed rectifier potassium current (IK) in cultured rat hippocampal neurons. Methods The effects of 17β-estradiol on Kv2. 1 channel current and IK in cultured rat hippocampal neurons were observed using the whole cell patch clamp techniques. Results 17β-Estradiol was shown to reduce the amplitude of Kv2. 1 current and IK in concentration-dependent manners. The IC50s of 17β-estradiol blocking Kv2. 1 and IK were 2.4 and 4.0μmol·L-1, respectively. 17β-Estradiol (3μmol·l-1) significantly shifted the steady-state activation and inactivation curves of Kv2. 1 current to negative potentials. However, it only produced the shift of the steady-state activation curve of IK to the negative potential without effect on the steady-state inactivation of IK. Conclusion 17β-Estradiol inhibits Kv2. 1 and IK of hippocampus at similar level. The inhibition of 17β-estradiol on IK current may be partially via blocking Kv2. 1 current.更多还原