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采用双电极电压钳技术观测了青蒿素对表达于非洲蛙卵的克隆内向整流钾通道（Ｋｉｒ２．１）的影响． 当蛙卵注射Ｋｉｒ２．１ ｃＲＮＡ 后灌注不同浓度青蒿素时， 青蒿素呈浓度依赖关系降低Ｋｉｒ２．１钾通道在非洲蛙卵细胞膜的功能表达． 青蒿素阻断Ｋｉｒ２．１钾通道亦呈电压依赖性．当指令电压为－ １４０，－ １３０和－ １２０ ｍ Ｖ 时， ５ 和５０ μｍ ｏｌ·Ｌ－ １ 的青蒿素可使Ｋｉｒ２．１钾通道的内向电流分别下降１４．２％ ， ３４．５％ ；１２．０％ ，２４．６％ ；４．３％ ，１９．１％ ．当指令电压为－ ５０， － ４０ 和－ ３０ ｍ Ｖ 时， ５ 和５０ μｍ ｏｌ·Ｌ－ １的青蒿素则使Ｋｉｒ２．１钾通道的外向电流分别增加２２．２％ ，７２．２％ ； ２８．０％ ， ８０．０％ ； ２４．１％ ， ６９．０％ ． 青蒿素对Ｋｉｒ２．１通道的阻断作用在用正常灌注液冲洗后可恢复． 青蒿素的抗心律失常作用与它阻断Ｋｉｒ２．１通道电流有关．
Two-electrode voltage clamp technique was used to observe the effect of artemisinin on cloned inward rectifier potassium channels (Kir2.1) expressed in African frog eggs. When artemisinin was infused at different concentrations after Kir2.1 cRNA was injected into frog eggs, artemisinin concentration-dependently reduced the functional expression of Kir2.1 potassium channel in the frog’s egg membrane. Artemisinin is also voltage-dependent in blocking Kir2.1 potassium channels. When the instruction voltages were -140, -130, and -120 mV, artemisinin at 5 and 50 μmol·L -1 decreased the inward current of Kir2.1 potassium channel by 14.2% and 34.5%, respectively. 12.0%, 24.6%; 4.3%, 19.1%. When the instruction voltages were -50, -40, and -30 mV, artemisinin at 5 and 50 μmol·L -1 increased the outward current of Kir2.1 potassium channel by 22.2% and 72.2%, respectively. 28.0%, 80.0%; 24.1%, 69.0%. The blocking effect of artemisinin on Kir2.1 channels can be restored after flushing with normal perfusate. The antiarrhythmic effect of artemisinin is related to its blocking of Kir2.1 channel current.