【摘要】 采用钙离子敏感中性载体ETH 1001研制成外径<0.7 um的钙离子敏感微电极(Ca²⁺—ISM),Ca²⁺浓度在10^-3～10^-7M之间,平均斜率为25.4 mV。检测下限为10^-8M。应用该Ca²⁺-ISM及常用微电极,同时测定了蟾蜍缝匠肌细胞内的钙离子活度α_Caⁱ和细胞膜电位（E_M）,测定结果为:α_Caⁱ=0.11um,E_M=-79.0mV。通过分别改变任氏液中的钾离子浓度[K⁺]。和钙离子浓度[Ca²⁺]。测定α_Caⁱ了及E_M的动态变化。结果表明:[K⁺],从3.5 mM升高至10 mM时,α_Caⁱ由0.11μM变为0.15 uM,E_M由-79.0mV变为-67.7 mV[Ca²⁺],从1.8mM降低为1μM时,α_Caⁱ由0.11 μM穸为0.03μM,E_M由-79.0mV变为-73.8mV。实验表明Ca²⁺-ISM是细胞内钙离子动态检测极为有效,方便和直观的方法之一。更多还原

【Abstract】 This paper decribes the use of the Ca²+-sensitive neutral carrier ETH 1001 to prepare calcium ion-sensitive microelectrode （Ca²+-ISM）. Its outer diameter is less than 0.7μm. Between pCa₃ 3（PCa3…） and 7, the per decade potential change in [Ca²+] of the Ca²+-ISM is 25.4mV and the lowest Ca²+ detecting concentration is 10^-8M. The intracellular Ca²⁺ activity (0_caⁱ) and cellular resting membrane potential （E_M） of frog’s sartorius muscle were detected simultaneously. The results showed that: α_caⁱ =-0.11μM, E_M =-79.0mV. By altering the potassiun ionic concentration[K⁺]₀ and calcium ionic concentration [Ca²⁺]₀ of Ringer’s solution, the dynamic changes of α_caⁱ, and E_M were measured. The results are as follows: （1） when [K⁺]₀ was increased from 3.5mM to 10.0mM, (α_caⁱ) increased from 0.11μM to 0.15μM, E_M fell from -79.0mV to-67.7mV; （2） when FCa²⁺]₀ was decreased from 1.8mM to 1.0mM, α_caⁱ decreased from 0.11μM to 0.03μM and E_M fell from -79.0mV to-73.8 mV. Our results also show that Ca²⁺-ISM is one of the direct, convenient and effective means in the dynamic detection of intracellular calcium ion.更多还原