Fig. 1. Retrograde labeling of neurons projecting into the NAc. (A) Experimental design and time schedule for CTB injection (green arrows) into the NAc. After 14 days of the surgery, 1-h restraint was treated. Red arrow, time point for tissue preparation. CON, CTB-injected control mice; RST, CTB-injected and stress treated mice. (B, C) A fluorescence image (B) of Alexa-conjugated CTB (cholera toxin subunit B) expression in the lateral core and shell of the NAc 14 days after the surgery and a schematic diagram (C) of CTB injection (left panel). Projections from the prelimbic cortex (PL), ventral hippocampus (vHIP), ventral tegmental area (VTA), and basolateral amygdala (BLA) are indicated. acc, anterior commissures; core, NAc core; ISh, lateral shell of the NAc; mSH, medial shell of the NAc. Scale bar, 500 µm. (D) Schematic diagram illustrating endocytosis of CTB at the synaptic terminal and retrograde transport of fluorescent CTB along the axon and its translocation into the cell body region (adapted from [63, 64]). (E~G) CTB-positive cells in the PL (E), BLA (F), and vHIP (G). Schematic diagrams illustrating the coronal sections at the level of the PL (E), BLA (F), and vHIP (G). High magnification of the areas marked with a rectangle. Cg, cingulate cortex; fmi, anterior forceps minor of the corpus callosum; VI/V, cortical layers VI/V; II/III, cortical layers II/III; BLA, basolateral amygdala; CeA, central amygdala. Scale bars; 50 µm in the PL and BLA, and vHIP.
© Exp Neurobiol
