Imaging Striatal Dopamine Release Using a Non-Genetically Encoded Near-Infrared Fluorescent Catecholamine Nanosensor

Abraham G. Beyene; Kristen Delevich; Jackson Travis Del Bonis-O’Donnell; David J. Piekarski; Wan Chen Lin; A. Wren Thomas; Sarah J. Yang; Polina Kosillo; Darwin Yang; Linda Wilbrecht; Markita P. Landry

In order to understand how neuromodulation alters the plasticity and activity of distinct populations of neurons, there is need for new optical tools that can measure the extracellular dynamics of neuromodulator release and reuptake at spatiotemporal resolution commensurate with methods used to record neural activity (e.g. electrophysiology and calcium imaging). Here, we demonstrated the feasibility of using of a non-genetically encoded fluorescent sensor, nIRCat, which enables optical detection of catecholamine release and reuptake with sub-second temporal and with micrometer spatial resolution. We used electrical and optogenetic methods in ex vivo brain slices to demonstrate that nIRCat fluorescent signals can successfully report differences in evoked dopamine release and pharmacologically induced changes in dopamine dynamics in striatal brain tissue.