Comparison of presynaptic puncta formation in cocultures of rat embryonic neural cells with MSCs or SB623; immunostaining. (A) Immunostaining for VGLUT (day 7) and VGAT (day 11); rat/human cell ratio, 50:1. Bar, 50 μm. (B) Quantification of VGAT-immunoreactive puncta per neurite length (averaged from 10 microscopic fields, one to four neurites/field), day 11. (C) Typical distribution and size of VGAT-positive puncta in axonal processes in cocultures with MSCs (upper) or SB623 (lower), day 13. Neurites are outlined manually. Bar, 50 um.