Figure 5.

A–F, Anatomical distribution of NPY and Y2 receptors and mRNA in the BLA and CEA. NPY and Y2 mRNA and protein were widely distributed within different amygdaloid nuclei. A dense NPY- (E) and Y2-receptor- (F) containing fiber tract arising from the CEA contributes to the stria terminalis (st). In G, a schematic drawing of the proposed Y2-containing projections is shown. Proposed sites of anxiolytic action of the Y2 deletion are the terminals of GABA/NPY interneurons in the BLA and the CEA, which project from the lateral part of the CEA (CEAl) to its medial extension (CEAm). Importantly, deletion of the Y2 receptor gene in the CEA causes deletion of Y2 receptors in the terminals of its projections, e.g., in the ncl. accumbens, stria terminalis/BNST, and locus ceruleus, where subsequent anxiolytic/antidepressant effects might be integrated. Glutamatergic projections are shown in black, GABAergic in red. Scale bars: B (for A–D), E, 500 μm; F, 100 μm.