Searches for new voltage-sensitive dyes

外部（需要电压敏感染料）光信号为监测活细胞的电活动提供了强有力的手段。事实上，利用光学技术和电压敏感染料，我们已经能够克服神经和心脏系统电生理研究的几个障碍。因此，用于测量膜电位快速变化的电压敏感染料的开发取得了很大进展。另一方面，传统的电压敏染料在使用过程中，其电压敏性和理化性质存在一些限制和困难。因此，我们尝试寻找新的电压敏感染料，我们得到了以下结果。(1)广泛的染料筛选导致选择di-8-ANEPPS作为监测心脏动作电位的最合适的电压敏感染料：它内化缓慢，允许光学记录的信噪比高达40:1（测量峰对峰），每100 mV膜电位的平均荧光分数变化为15%。[与MBL的B.M.Salzberg和宾夕法尼亚大学合作]。(2)在胚胎脊髓中检测了7种苯乙烯染料di4-和di8- anepps（负固定电荷），di2-、di8-、di12-和di16-ANEPPQ（正固定电荷）。染料是用充满浓缩染料溶液的微电极加压注入腹根的。所有的疏水染料（<大于或等于> di8）似乎都能特异性标记运动神经元及其过程。所得结果表明，从特殊标记的中枢神经元群中可以获得相对较大的光信号。为了评估各种快速电压敏感染料在胚胎神经系统快速跨膜电位活动光学监测中的适用性，我们筛选了20多种染料，包括几种新合成的探针。然后，发现了几种有希望用于胚胎神经系统的新型merocyanine-rhodanine染料。[在我们的实验室]更少

Extrinsic (requiring voltage-sensitive dyes) optical signals have provided a powerful means for monitoring electrical activity of living cells. Indeed, using optical techniques and voltage-sensitive dyes, we have been able to overcome several obstacles to the electrophysiological study of nervous and cardiac systems. Therefore, much progress has been achieved in the development of voltage-sensitive dyes for measurements of rapid changes in membrane potential. On the other hand, in using of conventional voltage-sensitive dyes, there are several limitations and difficulties in their voltage-sensitivity and physicochemical properties. Thus, we have tried to search for new voltage-sensitive dyes, and we have obtained the following results.(1) Extensive dye screening led to the choice of di-8-ANEPPS as the most suitable voltage-sensitive dye for monitoring cardiac action potentials : it is internalized slowly and permits optical recording with signal-to-noise ratio as high as 40 : 1 (measur … More ed in peak-to-peak) and average fractional fluorescence change of 15 % per 100 mV of the membrane potential. [with B.M.Salzberg in the MBL and University of Pennsylvania].(2) We tested seven styryl dyes di4- and di8-ANEPPS (negative fixed charge), di2-, di8-, di12-, and di16-ANEPPQ (positive fixed charge), in the embryonic spinal cord. The dyes were pressure-injected into ventral roots using a microelectrode filled with a concentrated dye solution. All the more hydrophobic dyes (<greater than or equal> di8) appeared to specifically label motor neurons and their process. The obtained results suggest that relatively large optical signals may be obtained from specially labeled populations of central neurons. [with L.B.Cohen in the MBL and Yale Un(3) To evaluate the suitability of a variety of fast voltage-sensitive dyes for optical monitoring of rapid transmembrane potential activity in the embryonic nervous system, we screened over twenty dyes, including several newly synthesized probes. And then, several promising new merocyanine-rhodanine dyes for embryonic nervous systems were found. [in our laboratory] Less