Arsenazo III and antipyrylazo III calcium transients in single skeletal muscle fibers.
Arsenazo III and antipyrylazo III calcium transients in single skeletal muscle fibers.
复制标题
单骨骼肌纤维中的胂 III 和安替吡唑 III 钙瞬变。
DOI：
10.1085/jgp.79.4.679
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
Vergara,J
中科院分区：
文献类型：
--
作者：
Palade,P;Vergara,J
金属铬钙指示剂偶氮胂III和安替比林偶氮III已被单独引入切割的单青蛙骨骼肌纤维，从其中钙瞬变已引起的动作电位刺激或电压钳脉冲的持续时间高达50毫秒。当由动作电位引起时，用两种染料在选定波长下记录的钙瞬变具有相似的特征。更长的电压钳脉冲刺激揭示了用两种染料获得的光学信号后期的差异。实验比较了不同张力阻断方法对Ca瞬变的影响。EGTA的浓度高达3 mM的内部应用被证明是有效的，在不影响钙瞬变阻断运动伪影。较高的EGTA浓度影响Ca信号的特征。内部应用EGTA对张力发展的差异效应，而不是钙瞬变表明，从Ca++释放位点的细丝重叠位点的结合扩散可能是显着的。用偶氮胂III记录的吸光度瞬变的光谱特性表明，在原位记录的信号不能很容易地解释在钙浓度的变化。需要对染料化学和/或染料使用中的原位并发症有更详尽的了解。
The metallochrome calcium indicators arsenazo III and antipyrylazo III have been introduced individually into cut single frog skeletal muscle fibers from which calcium transients have been elicited either by action potential stimulation or by voltage-clamp pulses of up to 50 ms in duration. Calcium transients recorded with both dyes at selected wavelengths have similar characteristics when elicited by action potentials. Longer voltage-clamp pulse stimulation reveals differences in the late phases of the optical signals obtained with the two dyes. The effects of different tension blocking methods on Ca transients were compared experimentally. Internal application of EGTA at concentrations up to 3 mM was demonstrated to be efficient in blocking movement artifacts without affecting Ca transients. Higher EGTA concentrations affect the Ca signals' characteristics. Differential effects of internally applied EGTA on tension development as opposed to calcium transients suggest that diffusion with binding from Ca++ release sites to filament overlap sites may be significant. The spectral characteristics of the absorbance transients recorded with arsenazo III suggest that in situ recorded signals cannot be easily interpreted in terms of Ca concentration changes. A more exhaustic knowledge of the dye chemistry and/or in situ complications in the use of the dye will be necessary.