Effect Of Shock Wave On NMJ And Muscle Morphology In Rabbits

Objective:Evaluate the AChE and nAChR in the NMJ and the morphology of the muscle in the bilateral triceps surae after unilateral shock wave therapy.Methods:60 male New Zealand rabbits weighing 2 0.2Kg were selected for the animal experiment.Two thousand shock waves at an energy flux density of 1.5bar and the frequency of 10Hz were applied to their left calf muscles.Divided into six groups,the both sides of the triceps muscle of calf was take out on the day of the shock wave and the1,2,4,6 and 8 weeks after treatment,HE staining was used to observe the morphological changes of muscle tissue,the average optical density be measured after AChE stain,calculated the receptor count after Acetylcholine receptor immunohistochemistry.In the clinical trial,23 patients with spinal cord injury accompanied by spasm were selected,and 2000 shocks of 2bar intensity and 10Hz frequency were applied to the lateral head of bilateral gastrocnemius muscle,and the CMAP amplitude and latency were compared before and after the shock wave treatment.Results:No abnormal morphological abnormalities were observed in all rabbits In the first five groups,the AChE was significantly higher in the side of the shockwave treatment compair with the control side(P<0.05),slow decrease after 1 week after treatment.In the first five groups,the nAChR was significantly lower in the side of the shockwave treatment compair with the control side(P<0.05),and gradually increased to normal after 8 weeks.CMAP amplitude was significantly reduced after shock wave treatment in all patients in clinical trials.Conclusion:Suitable dose of shock wave will not have a greater impact on morphology of muscle tissue.After the shock wave treatment,the amount and degree of stimulate of muscle cells were decreased,and reduces the production of action potentials.While the experimental side AchE and AchR in shock wave treatment day to 8 weeks after treatment showed a significant trend to normal,shows that the effect of shock wave on NMJ is transient and reversible.Combined with the results of previous experiments and clinical trials,the effects of shock wave on normal and spasmodic muscle tissues were similar.