Dopamine in the ventral tegmental area facilitates emergence from general anesthesia

Taylor et al. (1) showed that optogenetic activation of dopaminergic neurons in the ventral tegmental area (VTA) during continuous, steady-state isoflurane-induced general anesthesia produced electrographic arousal, and restored the righting reflex in mice. Systemic administration of the D1 receptor antagonist SCH-23390 before optical stimulation greatly attenuated electrographic and behavioral arousal. Transfection of VTA neurons with a vector carrying channelrhodopsin 2 (ChR2) allowed optical activation, and optical stimulation in control mice transfected with a vector lacking ChR2 did not induce arousal.