The present invention relates to a group of organic chelators whose affinity for calcium ion in solution is increased by electromagnetic radiation. Specifically, the chelators are related to BAPTA and utilize the addition of an electron-withdrawing group (e.g., diazocarbonyl) to a ring of BAPTA, para to the amino group. Photochemical rearrangement of the diazoacetyl group converts the group to the electron-donating carboxymethyl group, causing the calcium ion efficiency to increase 25 to 50 fold. These chelators when incorporated into rat fibroblasts either by microinjection or by incubation as the membrane-permeable, enzymatically-labile tetraacetoxymethyl ester and flash-photolyzed cause a drop in intracellular free calcine ion to or below resting valves of about 10.sup.-7 M. These chelators are used to generate controlled fast removal of intracellular free calcium ion to mimic or modulate a number of important cellular responses, especially in nerve or muscle.
本发明涉及一组有机
螯合剂,其在电磁辐射下对溶液中的
钙离子的亲和力增加。具体而言,这些
螯合剂与BA
PTA相关,并利用向BA
PTA环中的
氨基基团的对位处添加一个电子吸引基团(例如,重氮羰基)。重氮乙酰基团的光
化学重排将该基团转化为电子供体的羧甲基基团,使
钙离子效率增加25至50倍。这些
螯合剂被微注或作为可渗透膜、酶敏感的四乙酰甲基酯孵育后加入到大鼠成纤维细胞中,并通过快速光解引起细胞内游离
钙离子的降低到或低于约10^-7 M的静息值。这些
螯合剂用于产生控制性的快速去除细胞内游离
钙离子,模拟或调节许多重要的细胞反应,特别是在神经或肌肉中。