Figure 2.

A subset of VTA LepR neurons are glutamatergic or GABAergic. Immunostaining of pSTAT3 was performed on brain sections of mice that received i.c.v. injection of leptin. These mice also received stereotaxic injections to the VTA of AAV-FLEX-GFP vectors to allow labeling of Cre-expressing neurons with GFP. Expression of GFP (A, D) and p-STAT3 (B, E) was found in the VTA of Vgat-Ires-Cre mice (A–C) and Vglut2-IRES-Cre mice (D–F). p-STAT3 positive neurons were found in a subset of GFP-expressing neurons in both Vgat-Ires-Cre mice (C, arrows) and Vglut2-IRES-Cre mice (F, arrows). IP, interpeduncular nucleus; ml, medial lemniscus. Scale bars, 25 μm.