Fig. 6.

Evidence for local glutamatergic innervation of LC area GABAergic neurons. VGlut2-ires-Cre mice were unilaterally injected near the LC with AAV encoding Cre-dependent barley lectin 3 wk before they were euthanized, and sections through the LC area were labeled with antibodies to dopamine beta hydroxylase (DBH, green), BL (cyan), and GABA (red). Note the distribution of BL-ir on the virus-injected side (A, arrow). B–E show high magnification images of DBH-ir (B), BL-ir (C), GABA-ir (D), and a merged image (E). Arrows point to multiple GABA neurons surrounding the LC and colocalized BL-ir. Arrowheads point to non-GABAergic neurons colocalized with BL-ir. None of the DBH-ir neurons shown on this section contain BL-ir. 4V, fourth ventricle; 7N, seventh cranial nerve; BR, Barrington nucleus; LC, locus ceruleus; MPB, medial parabrachial nucleus. (Scale bars: A, 200 μm; B–E, 20 μm.)