Figure 5.

Soluble BMP antagonists inhibit BMP-5-induced dendritic growth. Beginning on the fifth day in vitro, SCG neurons were exposed to BMP-5 (100 ng/ml) in the absence or presence of varying concentrations of follistatin (A), noggin (B) or the BMP-RIA-Fc chimera (C). On the tenth day in vitro, cultures were immunostained with mAb to nonphosphorylated forms of the M and H neurofilaments to visualize dendrites. Dendritic growth was quantified with respect to the number of dendrites per neuron expressed as the mean ± S.E.M. (n = 50 per experimental condition). ^* Indicates a significant difference from negative control values (- BMP-5/- antagonist) indicated by the dashed line in each bar graph at p < 0.01 and ^** from positive control values (+ BMP-5/- antagonist) at p < 0.01.