THE EFFECTS OF PH AND TEMPERATURE ON FLUORESCENT CALCIUM INDICATORS AS DETERMINED WITH CHELEX-100 AND EDTA BUFFER SYSTEMS
THE EFFECTS OF PH AND TEMPERATURE ON FLUORESCENT CALCIUM INDICATORS AS DETERMINED WITH CHELEX-100 AND EDTA BUFFER SYSTEMS
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DOI：
10.1016/0006-291x(90)91362-v
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发表时间：
1990-08-31
影响因子：
3.1
通讯作者：
LATTANZIO, FA
中科院分区：
文献类型：
--
作者：
LATTANZIO, FA
本文介绍了一种利用Chelex-100离子交换树脂和~（45）Ca测定钙荧光指示剂表观离解常数的新方法。在22 ℃下测量的指示剂fluo-3、fura-2和indo-1对钙的亲和力。或37 °。C随着pH从7.4降低到5.5而降低。这些测量结果与使用EDTA-钙缓冲液进行的测定一致。在所有条件下均保持1：1的钙：指示剂复合物。在细胞内酸化正确解释荧光测量的必要性，以正确的解离常数说明在缺血大鼠心脏的indo-1测量。
A novel method of determining the apparent dissociation constants of fluorescent calcium indicators is described which utilizes Chelex-100 ion exchange resin and 45Ca. The affinity for calcium of indicators fluo-3, fura-2 and indo-1 measured at either 22.degree. or 37.degree. C decreases as pH is decreased from 7.4 to 5.5. These measurements agree with determinations made using EDTA-calcium buffers. The 1:1 calcium:indicator complex is maintained under all conditions. The necessity to correct dissociation constants during intracellular acidification to properly interpret fluorescence measurements is illustrated by indo-1 measurements in the ischemic rat heart.