Niacin increases neurite outgrowth in PCNs after OGD. A–H: Neurite outgrowth in the PCNs (A, Control; B, HDL 80μg/ml; C, Niacin 1mM; D, Niacin 5mM; E, TrkB 200nM; F, TrkB-inhibitor + HDL; G, TrKB-inhibitor + Niacin 1mM; H, TrKB-inhibitor + Niacin 5mM); I: Quantitative data of PCN neurite outgrowth (n=6/group). J: Quantitative data of PCN numbers (n=6/group). Scale bar in A = 40μm.