The rostral-caudal extent of transgene expression was assessed by immunohistochemistry. Brain sections were immunostained as previously described (Guggenhuber et al., 2010 (link)) using a rabbit anti-HA primary antibody (Santa Cruz Biotechnology, Santa Cruz, CA; 1:1000). For colocalization studies, rabbit anti-MAGL (generous gift from Ken Mackie, 1:200), guinea pig anti-VGluT1 (Millipore, 1:500), and rabbit anti-CB1R (Frontier Institute, Hokkaido, Japan, 1:500) primary antibodies were used.