Rat hippocampal neurons were plated on glass coverslips and inverted on top of astrocytes (previously untreated or treated with DZ for 24 h) for 48 h. Neurons were then fixed and stained with a neuron-specific tubulin antibody, and analyzed for (A) longest neurite length, (B) minor neurite length, and (C) number of neurites per cell. Results represent the mean (± SEM) of 90-120 cells derived from at least three separate experiments. Significantly different from untreated control, *p<0.05, ***p<0.001.