Figure 5.
Neurite outgrowth in cocultures is downregulated by estrogen and rescued by exogenous BMP4. A, Smooth muscle cells (unstained) were grown for 72 h, on which dissociated sensory neurons (green) were cultured for 48 h. Scale bar: A–C, 50 μm. B, When smooth muscle cells were grown in the presence of 2 × 10−8 m 17β-estradiol, neurite outgrowth appeared to be reduced. C, Addition of 10 ng/ml recombinant BMP4 appeared to increase numbers of neurites. D, Quantitative analysis showed that neurite outgrowth per neuron was reduced by estrogen (E2) pretreatment (*p = 0.001 vs control), and the decrease was abrogated by BMP4 (#p = 0.004 vs E2). There was no significant difference between control and E2 + BMP4.