Fig. 5

RhoA/Rho-kinase was required for the maintenance of neuronal polarity. a Local inhibition of Rho-kinase induced minor neurite elongation. DMSO (top) or Rho-kinase inhibitor (Y-27632) (bottom) was locally applied to a minor neurite of a polarized hippocampal neuron. b Local application of Y-27632, C3 or Blebbistatin to a minor neurite. Minor neurite outgrowth was measured (Cont = 17, Y-27632 = 14, C3 = 13, Blebbistatin = 7 neurons from three independent experiments). c The effect of the RhoA/Rho-kinase signaling pathway on neuronal polarization. Hippocampal neurons at 3 DIV were treated with Y-27632, C3 or lebbistatin for 48 h. Neurons were co-immunostained at 5 DIV with anti–Tau-1 (magenta) and anti–MAP2 (green) antibodies. Representative images of neurons are shown. Scale bar, 100 μm. d The percentages of neurons with multiple Tau-1-positive axons. e Bar graphs indicate the ratio of multiple axonal lengths. f, g The lengths of the longest neurite f and the total neurites g were determined (Cont = 91, Y-27632 = 90, C3 = 90, Blebbistatin = 91 neurons from three independent experiments). Error bars represent SEM. *P < 0.05 and **P < 0.01