Optical dissection of cardiac electrophysiology
Here we aredeveloping innovative optical approaches to simultaneously probe and control the crucial determinants of cardiac function. Ultrafast deflectors are used to rapidly scan laser beams across the sample, performing multiplexed optical measurements of action potential and Ca2+ release from multiple sites within cardiac cells and tissueswith submillisecond temporal and submicrometer spatial resolution in real time.The same scanning modality are also used to control local Ca2+ release and membrane electrical activity by activation of caged compounds and light-gated ion channels. The spatiotemporal relationship between voltage and Ca2+ (excitation-contraction coupling, ECC) are investigated at different hierarchical levels, from single isolated cardiomyocytes to intact heart tissue. Local Ca2+ or voltage perturbations can be induced, simulating arrhythmogenic events, and their impact on physiological cell activity can be explored.The development and the application of these complementary optical methodologies will provide fundamental insights cardiac disease and will represent a whole new approach for the investigation of the physiology of the heart.