부산대학교 도서관

Background: Behavioral recovery may be the most important functional evidence of axon regeneration following peripheral nerve injury. The CatWalk system had been reported to simultaneously measure dynamic and static gait parameters in rats with sciatic nerve crush injury, but this method has not yet been adapted to the mouse model. Aim and Objectives: Using CatWalk gait analysis to assess functional recovery in a mouse model of sciatic nerve crush injury Materials and Methods: CatWalk gait analysis was performed pre- and postoperatively in 10 C57BL/6 mice that underwent a standard crush injury model with No. 5 Jeweler's forceps for 30 seconds in the right sciatic nerve, and the results were compared with those for a sham control group. The print length factor (PLF); toe spread factor (TSF); sciatic static index in mice (SSIm); and static paw parameters including individual paw parameters, intensity, maximum contact area of the hind paws, and dynamic paw parameters (swing duration, stance duration, and duty cycle) were measured and analyzed. An additional group of mice was used for western blotting at different time points during nerve regeneration to detect changes in myelin protein zero (MPZ) expression in the sciatic nerve distal to the crush site. Results: MPZ expression started to decrease on postoperative day 3 and returned to normal levels at day 17 and thereafter. We observed unexpected changes in the print width, print area, intensity, maximum contact area, time of stance phase, and duty cycle shortly after the sham operation. In addition, we noted high variability in PLF, print width, print area, intensity, maximum contact area, and duty cycle during nerve regeneration, which hampered the application of these measurements. The only CatWalk gait analysis parameters that consistently yielded useful results after sciatic nerve crush injury were TSF, SSIm, print length, and time of swing phase measured for the hind paws. Conclusion: Some, but not all, gait parameters measured by the CatWalk gait analysis are suitable for assessing behavioral recovery after sciatic nerve crush injury in mice.