Figure 17.

(a) Two-photon activates of individual neurons present in mouse brain slices with C1V1T. (i) The experimental scheme shows the opsin C1V1T and EYFP genes encoded by Adeno-associated virus (AAV) are inserted in the somatosensory cortex of the mouse. Brain slices were prepared at a designated time point from the infected region. (ii) Two-photon fluorescence image of a living cortical brain slice expressing EYFP (940-nm excitation, 15 mW on the sample, 25×/1.05-NA objective; scale bar, 100 μm). (iii, iv) Magnified images from (b) show cells with C1V1T-expression present in higher (iii) and lower (iv) layers (scale bars, 20 μm (iii), and 10 μm (iv) Reprinted with permission from [180]. (b) Illustrative two-photon highest intensity projections of Alexa 594 fluorescence and current responses against a single 150 ms temporal focusing (TF) stimulation pulse (red bar) for patched and dye-filled pyramidal cells present in acute slices expressing targeted (T) and nontargeted (N) ChR2. Scale bar = 100 mm. Reprinted with permission from [181].