title: Modulating dopamine release by optogenetics in transgenic mice reveals terminal dopaminergic dynamics.
abstract: Dopamine (DA) release and uptake dynamics in the nucleus accumbens (NAc) have important implications for neurological diseases and mammalian animal behaviors. We demonstrate here the use of cell-type-specific optogenetic targeting in conjunction with fast-scan cyclic voltammetry applied to brain slices prepared from specifically tailored transgenic mice, which conditionally express channelrhodopsin-2 (ChR2) through dopamine transporter (DAT)-Cre. Terminal dopaminergic dynamics and the direct manipulation of induced DA release level by controlling light intensity, pulse width, and the shape of stimulation waveforms were studied. Effective cell terminal-targeting optogenetic induction of DA release at physiological levels in NAc is demonstrated and discussed. It was found that delivering more light energy by increasing stimulation intensity and length is not the only way to control DA release; the temporal shape of the stimulus waveform at light onset is also critically related to induced DA concentrations. In addition, DA uptake dynamics as well as the recovery of the presynaptic releasable DA pool are studied and modeled. More broadly, our experimental findings provide important further evidence for effectively applying optogenetics to induce neurotransmitter release in the behaviorally relevant region of the brain in a highly cell-type selective context.
authors.affiliation: Brown University , School of Engineering, Providence, Rhode Island 02912, United States ; Brown University , Department of Chemistry, Providence, Rhode Island 02912, United States.
authors.forename: Yao
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Brown University , School of Engineering, Providence, Rhode Island 02912, United States.
authors.forename: Nicolette
authors.initials: N
authors.lastname: Driscoll
authors.affiliation: Brown University , School of Engineering, Providence, Rhode Island 02912, United States.
authors.forename: Ilker
authors.initials: I
authors.lastname: Ozden
authors.affiliation: Brown University , School of Engineering, Providence, Rhode Island 02912, United States.
authors.forename: Zeyang
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Brown University , School of Engineering, Providence, Rhode Island 02912, United States ; Brown University , Institute of Brain Science, Providence, Rhode Island 02912, United States.
authors.forename: Arto V
authors.initials: AV
authors.lastname: Nurmikko
keywords: dopaminergic dynamics; fast scan cyclic voltammetry; nucleus accumbens; optogenetics