Activating Acid-Sensing Ion Channels with Photoacid Generators.

Acid-sensing ion channels (ASICs), present in both central and peripheral neurons, respond to changes in extracellular protons. They play important roles in many symptoms and diseases, such as pain, ischemic stroke and neurodegenerative diseases. Herein, we report a novel approach to activate ASICs with the precision of light using organic photoacid generators (PAGs), which are molecules that release H+ upon light illumination, and have been recently used in biomedical studies. The PAGs showed low toxicity in dark conditions. Under LED light illumination, ASICs activation and consequent calcium ion influx was monitored and analysed by fluorescence microscopy, and showed a strong light-dependent response. This approach allows the activation of ASICs with the precision of light, and may be valuable to help better elucidate the molecular mechanism of ASICs and unveil their roles in physiology, pathophysiology, and behaviour.