Optogenetic Activation of the Excitatory Neurons Expressing CaMKIIα in the Ventral Tegmental Area Upregulates the Locomotor Activity of Free Behaving Rats
Figure 1
Histology and in vivo electrophysiology for verification of the optogenetic studies. (a) Sketch of the AAV vector used for the optogenetic transductions in this study. (b) The centers of viral-delivery regions (the red circular dots) and the placements of optical fiber tips (the blue triangular dots) for all the optogenetic rats ( for the free-moving tasks, for the lever-pressing tasks, and for erroneous displacements). These two series of dots were measured by individually locating the traces of optrode fiber tips and of the microinjector observed under microscopy. Both series of traces were measured in the targeted brain slices with mm from Bregma and overlapped into the atlas of Paxinos and Watson. (c) A typical view of the ChR2-mCherry expressions on the neurons expressing CaMKIIα in and around the brain region of VTA that was overlapped with the brain atlas. (d) An inner set of (c) obtained from the region of interest (ROI) from the VTA region (including VTAR and PBP). ((e)-(f)) In vivo electrophysiology recorded from the implanted optrode device. The blue bar shown in both figures represents a shot of laser stimulations with 15 ms pulse width, 50 Hz frequency, 1.0 s duration, and a light power around 1 mW. (e) presents spike activities from all the sixteen channels of the optrode device where each short straight bar represents one spike firing, and (f) is the LFP signals recorded from four typical channels of the optrode device.
