Figure 4.

SNX17 expression was decreased in the gastrocnemius muscle of EAMG mice, and AChR was fragmented at the NMJ. (A) Representative mice in the normal group (upper left) and the EAMG group (lower left); weight gain in mice in each group between 1 and 11 weeks (right panel). NC: n = 6; SC: n = 5; EAMG: n = 26. (B) Lennon grading method to clinical score myasthenic symptoms in mice in each group. NC: n = 6; SC: n = 5; EAMG: n = 26. (C) Hanging time of mice in each group was measured by the flip suspension test. NC: n = 6; SC: n = 5; EAMG: n = 26. (D) Hanging time of 10 randomly selected EAMG mice before and 20 min after injecting neostigmine, measured by the flip suspension test. n = 10/group. (E) Concentration of AChR-Ab in serum was detected using ELISA. NC: n = 6; SC: n = 5; EAMG: n = 26. (F) EMG of the gastrocnemius muscle was determined using low-frequency RNS. The attenuation rate of the fifth amplitude of EMG compared with the first amplitude was calculated. NC and SC: n = 3/group; EAMG: n = 10. Western blotting analyses of the expression levels of (G) SNX17, and (H) LRP4, MuSK, and p-MuSK in the mouse gastrocnemius muscle tissue. n = 3/group. (I) AChR (red) at the NMJ of the gastrocnemius filaments was labeled with R-BTX and the area of AChRs was quantified with ImageJ. n = 5/group; Scale bar = 50 μm. All data are presented as mean ± SEM. *P<0.05, **P<0.01, ***P<0.001. AChR, acetylcholine receptor; EAMG, experimental autoimmune myasthenia gravis; LRP4, low-density lipoprotein receptor-related protein 4; MuSK, muscle-specific receptor tyrosine kinase; NC, normal control; NMJ, neuromuscular junction; R-BTX, rhodamine-labeled bungarotoxin; RNS, repetitive nerve stimulation; SC, solvent control; SEM, Standard Error of Mean; SNX17, sorting nexin 17.