Fig. 4: Comparison of the efficiency of 4 retrograde vectors when combined with anterograde AAV1-DIO-ChR2-EYFP.

The EYFP expression in neurons with double infection by anterograde AAV1-DIO-ChR2-EYFP and a retrograde vector was visualized with immunostaining with Ni-DAB. The arrangement was the same as in Fig. 2.