Fig. 4.

Culturing FDB muscles ex vivo resolves Wld^S and control phenotypes. (A) Tibial nerve (TibN)/FDB muscle preparation pinned to a Sylgard chamber, used for the ex-vivo culture and subsequent electrophysiological analysis. (B, C) Representative electrophysiological recordings from wild-type (B) and Wld^S (C) FDB muscle fibers, after 24 h culture ex vivo. (D, E) Confocal images of motor nerve terminals from thy1.2YFP16C57:Bl6 (D) and thy1.2YFP16:Wld^S (E) lumbrical muscles, 24 h after ex vivo culture at 32 °C. Images digitally adjusted for overall brightness and contrast only. (F) Time course of loss of innervation as measured electrophysiologically from the incidence of FDB muscle fibers responding with EPPs to nerve stimulation in Wld^S (filled bars) and wild-type mouse muscles. (G) Comparable incidences of occupied NMJ assayed in DL muscles morphologically using fluorescence microscopy. Both graphs show mean ± S.E.M., in n = 2–17 muscles.