Adult born neurons express CR, CB, and TH. 40× images with arrowheads indicating double positive cells for BrdU (red) and the subtypes CR, CB, and TH (green). Scale bars, 37 μm. (A and B) BrdU co-labels with CR in the GLL (A) and the GCL (B). BrdU co-labels with CB (C) and TH (D) in the GLL. CB, calbindin; CR, calretinin; TH, tyrosine-hydroxylase; GLL, glomerular layer; GCL, granule cell layer.