A Potentiometric Dual‐Channel Microsensor Reveals that Fluctuation of H2S is Less pH‐Dependent During Spreading Depolarization in the Rat Brain

Abstract Spreading depolarization (SD) is one of the most common neuropathologic phenomena in the nervous system, relating to numerous diseases. However, real‐time monitoring the rapid chemical changes during SD to probe the molecular mechanism remains a great challenge. We develop a potentiometric dual‐channel microsensor for simultaneous monitoring of H 2 S and pH featuring excellent selectivity and spatiotemporal resolution. Using this microsensor we first observe real time changes of H 2 S and pH in the rat brain induced by SD. This changes of H 2 S are completely suppressed when the rat pre‐treats with aminooxyacetic acid (AOAA), a blocker to inhibit the H 2 S‐producing enzyme, indicating H 2 S fluctuation might be related to enzyme‐dependent pathway during SD and less pH‐dependent. This study provides a new perspective for studying the function of H 2 S and the molecular basis of SD‐associated diseases.