A. Experimental paradigm and timelines. Chrimson-expressing mice underwent microdialysis over two consecutive days. Control mice (transfected with mCherry or eYFP) were dialyzed only on Day 1. B. Representative optical microscopy image of unilateral Chrimson-positive neurons in the substantia nigra and ventral tegmental area. The coronal brain atlas plate 58, adapted from The Mouse Brain in Stereotaxic Coordinates, Paxinos and Franklin, 2nd
edition (2001) Academic Press, is overlaid on the hemisphere contralateral to transfection. Ventral tegmental area (VTA), substantia nigra pars compacta (SNc), and substantia nigra pars reticulata (SNr) C. Model showing the location of the microdialysis probe in the dorsal striatum (dSTR) relative to Chrimson transfection and optical stimulation in the ipsalateral VTA, SNc, and SNr. Ventral striatum (vSTR), artificial cerebrospinal fluid (aCSF).