RESUMEN
Objective To assess the functional changes of the hind paw after SD rats being cut offthe L5 spinal nerve by CatWalk gait analysis.Methods Eleven male SD rats were chosen; the right side of these rats,as the experimental side,was cut the ventral root and dorsal root of L5 spinal nerve,while the left side was without any operation.One day after the operation,whether the models were successfully constructed was verified by tracer experiment with wheat germ agglutinin horseradish peroxidase (WGA-HRP) in 3 rats; 1 day before the operation and 3 months after the operation,the changes of such parameters as general parameters,individual paw parameters,pain-related parameters and coordination-related parameters were assessed by using CatWalk gait analysis.Results The WGA-HRP-labeled motoneurons and fibers were not found in posterior horn and anterior horn of the experimental side of L5 spinal gray matter,but both located in the left side,indicating that the models were constructed successfully.General parameters,individual paw parameters and pain-related gait parameters could be recorded 3 months after the operation,but no statistically significant difference was noted as compared with those 1 day before the operation; however,significant decrease of values of regularity index (RI) and coupling diagonal right after-left front in rats 3 months after the operation was noted as compared with those 1 day before the operation (P＜0.05).Conclusion Only a part of coordination-related gait parameters (the lower limbs) is influenced after being cut L5 spinal nerve;therefore,L5 spinal nerve can be used for constructing of a bladder reflex arc.