Figure 1. Transient weakness in the ClCadr mouse model of recessive myotonia.
(A) Shown is a force trace from a triceps surae muscle group of an unaffected littermate in response to stimulation of the sciatic nerve with 45 pulses at 100 Hz. (B) The force trace generated by following the initial stimulus with 15 pulses at 100 Hz delivered every 4 s. (C) In a ClCadr mouse, following the 45 pulses at 100 Hz (indicated by the dotted vertical line) there was continued force generation secondary to myotonia. (D) With stimulation every 4 s transient weakness was revealed. (E) Plot of the force normalized to force at 60 s in unaffected littermates and ClCadr mice. Transient reduction in force was present in ClCadr mice (*, p=0.00015 vs unaffected littermates at 16 s, t-test, 95% confidence interval 110–114 vs 75–93). n = 5 unaffected littermates and n = 9 ClCadr mice. Error bars represent ± SD.