Figure 4. Midbrain DA neurons do not express Gad1 or Gad2.
(A) Two-color in situ hybridization of Slc18a2 (Vmat2; top, red) and Gad1 (middle, green) demonstrates the absence of co-labeled DA neurons (bottom) in a coronal section through lateral VTA and SNc (dashed outline). Nuclei are stained blue. SNr, substantia nigra pars reticulata; D, dorsal; V, ventral; M, medial; L, lateral. (B) Representative high magnification confocal image of Slc18a2 (red) and Gad1 (green) expression in SNc. (C) Double fluorescence in situ hybridization for Slc18a2 and Gad1 exhibits considerable overlap in the tuberomamillary nucleus (TMN). (D and E) As in (A and B) for Slc18a2 (Vmat2) and Gad2 expression. (F) Slc18a2 and Gad2 expression co-localize in the A13 dopaminergic cell group.