Figure 7
Exogenous FGF8 supplementation in vitro rescues SMG branching morphogenesis. Paired E13 embryonic SMGs were preincubated for 3 hrs in 10 ng/ml FGFR2b-Fc chimera and then cultured for a total of 3 days with/without 500 ng/ml FGF8 peptide. A. E13+3 10 ng/ml FGFR2b-Fc-treated explant. B. E13+3 FGFR2b-Fc chimera + FGF8-treated explant. Bar, 30 μm. C. Comparison of Spooner ratios. A significant 20% (P < 0.001) decrease in branching morphogenesis with FGFR2b-Fc chimera abrogation was seen compared to IgG-Fc control. Exogenous FGF8 supplementation induced a significant 24% (P < 0.02) increase in branching to completely restore branching to the level seen in control.