Of Dexamethasone On Skeletal Muscle And Motor End Plates After Sciatic Nerve Injury Repair

Objective: Clamps the rat's sciatic nerve, to observe the effect of Dexamethasone on the morphologic changes of those skeletal muscle, motor end plate and enzyme activity of AchE under sciatic nerve's control, and study the therapeutic action of Dexamethasone for nerve injury.Methods:Wistar rats were divided into groups randomly.①Nerve injury group, the sciatic nerve injury model was established by clamping the nerve in the right.②Dexamethasone group, the dexamethasone was applied to injury side immediately.③Saline group, the saline was applied to the injury side instead of dexamethasone, after sciatic nerve injury.④Control group, raising rat without any treatment. Some specimens have been maken into paraffin section, and others into frozen section. The morphologic changes of skeletal muscle, motor end plate were observed with LM. We applied immunohistochemistry to survey enzyme activity changes of AchE, as well as made quantitative analysis by microscopic image analysis.Results:1. Morphologic observation shows thar the form of skeletal muscle recovered markedly with Dexamethasone, and the connective tissue obviously reduced. The structure of skeletal muscle changed obviously with mitochondria's getting back to normal, myofilament's arrangement rules and bubble's disappearance after Dexamethasone therapy.2. lmmunohistochemical shows that the Dexamethasone have a positive effect on SDH granulein skeletal muscle and enzyme particles of AchE in motor end plate.Conclusion:1. Dexamethasone can stable cellular structure of skeletal muscle, and promote its repair.2. The application of dexamethasone can improve the energy metabolism disorders of skeletal muscle caused by nerve damage.3. Dexamethasone can modify the enzyme activity and structural abnormalities of motor end plate arised from sciatic nerve injury.