Figure 5. MKP-5 deficiency in mdx mice leads to restored muscle function.

(A) Forelimb muscle strength measurement using a grip strength meter (Columbus Instruments). (B) EDL muscle–specific force. Tetanic contraction produced by stimulation at 100 Hz. (C) EDL muscle fatigue and relaxation. Muscles were subjected to a fatigue protocol consisting of a 1-second, 100-Hz tetanus every 2 seconds for a total of 30 seconds. Recovered force was measured by stimulating the EDLs for 250 milliseconds with 100-Hz pulses. Symbols that differ (#, §, ‡, or †) signify statistical significance at P < 0.05. Results are the mean ± SEM (n = 6 per genotype; 3-month-old male mice).