Calcium imaging in retinal research: challenges and prospects for its application

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Abstract

Calcium ions are universal signaling particles used alongside other signaling systems in animal cells. Changes in intracellular calcium concentration trigger vital reactions in different types of eukaryotic cells by acting through molecular calcium sensors. Over several decades, calcium imaging has been developed to study calcium-based signaling pathways. This method visualizes changes in intracellular free calcium using special fluorescent indicators. The retina, a type of nervous tissue in the eye, is responsible for perception, primary processing, and transmission of visual information to the brain. Signal cascades within retinal cells and synaptic transmission between cells play a crucial role in implementing these functions. Calcium plays a significant and diverse role in the functioning of the retina, in both normal and pathological conditions. Studying the fundamental processes of visual perception at the retinal level requires the visualization of changes in intracellular calcium concentration at different time scales, including very rapid changes. Consequently, the calcium imaging method, which was originally developed and used for studying other tissues, has now entered the field of visual neuroscience. While there are currently many examples of calcium imaging being used to study the functioning principles of all major types of retinal cells, adapting this method to the study of this tissue presents a number of difficulties. This review discussed these problems and how to solve them.

Keywords

calcium imaging / retina / vision / calcium intracellular signaling

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