Mechanism Of Influence Of TWP In Muscle Contractility And In Treatment Of EAMG

Myasthenis gravis (MG) is an autoimmune disease. It manifestsitself by varying weakness of muscle under voluntery control. Prednisone is one of the most effective treatments for MG. However, it has relatively severe side effects. A great deal of researchs has confirmed that Tripterygium Wilfordii Polyglycosidium (TWP) has strong anti-inflammatory and immunosuppressing effect. Clinical researchs have showed that TWP is a kind of safe and effective herb medicine in treating MG, which decreases or avoids side effects produced by such as glucocorticosteroid or cytotoxicity. Its scope of influence and effects has been increasingly received recognition. But we still know little about its specific mechanism. The studies, which have been done earlier in our research group, showed that TWP could increase muscle contraction by promoting the transmission at neuromusclar junction. However, there is no report reported about TWP's influence on capability of muscle contraction and also still lack of objective parameter about TWP's effect on MG. So this experiment aims at studying the effects and mechanism of TWP on capability of muscle contraction and compound muscle action potential, so as to understand TWP's influence and mechanism on muscle contraction more and establish a method and a kind of objective evidence for clinical treament on MG.This study consists of two parts:Part I : Effects of TWP on capability of muscle contraction of isolated gastrocnemius muscle preparation of toad were observed and recorded by using equilength transfering energy equipment.The results and conclusion are as follows:1. TWP not noly can stimulate the trasmission at neurornusclar junction, but also can enhance the inner ability of muscle contraction.2. Solvent DMSO can restrain muscle contraction.Part II: Experimental autoimmune myasthenia gravis (EAMG) was establited by injecting anitigen of AchR extracted from the muscle of calf; Influence of TWP on compound muscle action potential of gastrocnemius muscle and pronator teres muscle were observed and recorded by using neuroelectrophysiological method in established EAMG.The results and conclusion are as follows:1. EAMG was established successfully.2. TWP can increase the amplitude of compound muscle action potential of gastrocnemius muscle and pronator teres muscle.3. The effect of TWP on compound muscle action potential in different muscle has no different.4. TWP can enhence compound muscle action potential possibly not only by promoting transmission at neurornusclar junction but also by other mechanisms.5. Examining electromyography in more than one nerve-muscle groupcan increase diagnosis rate of MG.