Figure 3.

mAchR activity regulates oligodendrocyte commitment by hOPCs. CD140a/PDGFαR⁺ hOPCs were treated with 0–40 μm OxoM for 4 d and stained for O4 (red) and DAPI (blue) (a, b). The proportion of O4⁺ oligodendrocytes was determined at each dose (mean ± SEM, n = 3 seperate brain preparations, 19–22 week gestational age) (c). d–e, CD140a⁺ hOPCs were cocultured with human neuronal reaggregate cultures for 14 d in vitro (DIV). The fate of human OPCs was tracked by prior infection with mCherry-expressing lentivirus at −2 DIV. Oligodendrocyte differentiation was assessed at 14 DIV by colocalization of mCherry-expressing cells (red) with O4 (green) (d, null control). e, Daily treatment of matched cultures with 50 nm darifenacin, an M₃R antagonist, induced oligodendrocyte differentiation. f, Proportion of mCherry⁺ OPCs expressing O4 was determined (mean ± SEM, n = 3 separate brain preparations). *p < 0.05, t test. Scale bar, 50 μm.