FIGURE 4.

Overexpression of Fgf18 changed the direction of genioglossus muscle contraction. (A–D) Azon staining of sagittal sections of the genioglossus muscle in mice at E13.5. (E, F) Immunostaining with antibodies against Acta2 was performed on the sagittal sections of the E13.5 mouse embryos tongue. (G, H) Immunostaining with antibodies against Scx was performed on the tongue of mouse embryos at E13.5. (I, J) Immunostaining was performed on genioglossus muscle attachment sites of E13.5 mouse embryos using antibodies against Scx and Ki67. (K–N) Immunostaining with antibodies against Akt and Erk was performed on the tongue of mouse embryos at E13.5. (O) Quantification analysis of the percentage of Scx and Ki67 double-positive cells in the tongue tendon cells. m: Meckel cartilage, g: genioglossus, Scale bar = 200 µm (A–H, L–O), Scale bars = 100 μm (I, J). **p < 0.01.