James and Ricca have some words of caution for the field: they discovered that blue light can alter the fluorescent properties of the red dopamine sensor RdLight1 (a phenomenon akin to photoactivation) in a manner that may be misconstrued as phasic dopamine release. Dopamine measurements using the red-shifted fluorescent sensor RdLight1 should therefore be interpreted with caution when combined with optogenetics. In addition, their work strongly suggests that this artefactual photoactivation was erroneously interpreted to reflect cholinergic interneuron-evoked dopamine release in a prior study published in eLife. In light of this and other publications that did not observe large acetylcholine-evoked dopamine transients in vivo, the ability of cholinergic neurons to evoke dopamine release in vivo remains uncertain.
Commenti