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用膜片钳全细胞法研究关附甲素（ＧＡ）对单个心室肌细胞钠通道电流（ＩＮａ）的频率依赖性和使用依赖性影响。结果：４０μｍｏｌ／ＬＧＡ在刺激频率０．５，１．０，２．０Ｈｚ时使ＩＮａ峰值由用药前的７．９３±２．３ｎＡ分别降至４．８１±１．３，３．２３±１．１和１．２８±０．８ｎＡ（ｎ＝８，Ｐ均＜０．０５），抑制率分别是３９．３％、５９．３％和８３．９％。在脉冲串刺激时，维持电位－９０ｍＶ、指令电位－３０ｍＶ，灌流前ＩＮａ为７．６９±１．３３ｎＡ；４０μｍｏｌ／ＬＧＡ灌流后第１，１０，２０，３０个脉冲ＩＮａ分别是４．２４±０．９８，３．２５±０．７４，２．３３±０．６４和２．０６±０．７０ｎＡ（ｎ＝６，Ｐ均＜０．０１）；而在维持电位－８０ｍＶ，指令电位－３０ｍＶ时，ＧＡ灌流前ＩＮａ为７．５１±１．４３ｎＡ，在灌流后第１，１０，２０，３０个脉冲分别是４．１９±１．０９，２．２８±０．４１，１．２７±０．２４和０．８９±０．２５ｎＡ（ｎ＝６，Ｐ均＜０．０１）。提示：ＧＡ抑制ＩＮａ具有频率依赖性及使用依赖性，其频率依赖性和使用依赖性的机理相同。
Whole-cell patch-clamp method was used to investigate the frequency-dependent and dependence-dependent effects of guanosine-1 (GA) on sodium channel current (INa) in isolated ventricular myocytes. Results: The peak value of INa was decreased from 7.93 ± 2.3nA before treatment to 4.81 ± 1.3,3.23 ± 1 at 40μmol / LGA at stimulation frequency of 0.5,1.0,2.0Hz .1 and 1.28 ± 0.8nA (n = 8, P <0.05). The inhibition rates were 39.3%, 59.3% and 83.9% respectively. In pulse train stimulation, the holding potential -90mV, the command potential -30mV, pre-perfusion INa was 7.69 ± 1.33nA; 40μmol / LGA perfusion after the 1st, 10th, 20th and 30th pulse INa were 4.24 ± 0.98,3.25 ± 0.74,2.33 ± 0.64 and 2.06 ± 0.70nA (n = 6, P <0.01), while at the maintenance potential of -80mV, the command potential- At 30mV, the INa before GA perfusion was 7.51 ± 1.43nA, and the 1st, 10th, 20th and 30th pulses after perfusion were 4.19 ± 1.09,2.28 ± 0.41,1.27 ± 0.24 and 0.89 ± 0.25 nA (n = 6, P <0.01). Hints: GA inhibits INa in a frequency-dependent and usage-dependent manner, with the same mechanism of frequency dependence and dependence.