| Group B Coxsackieviruses ( CVB) , single-stranded UNA viruses, belonging to the enterovirus genus of Picornaviridae, are major pathogens of viral myocarditis. Serology and epidemiology showed that 25% -50% patients with acute myocarditis had recent or recurrent CVB infection. Incidence of viral myocarditis in children was a little high, and Coxsackievirus infection in newborn had been reported abroad frequently to which pediatric scholars had paid more attention. In china such as Beijing, Huangshan, Shenyang and so on, different scope of epidemic CVB infection occurred, characterized mainly by myocarditis and, or aseptic meningitis, but up to today no effective medicine have been found, resulting in high fatality rate of this disease in newborn. So developing effective medicine to prevent from maternal-fatal CVB infection and protect children health has important meaning.It is now well established that immune effector mechanisms contribute to cardiomyopathy in myocarditis. These and other pathologies, in which cellular immunity plays an important role, contribute to morbidity and mortality worldwide. As a result of numerous studies performed in this exciting field, two major mechanisms of lymphocytotoxicity have been proposed: a secretory mechanism inwhich perform and granzymes axe key players, and a non-secretory mechanism involving Fas/FasL activation. While the common notion is that CTL-myocyte interaction, perform- or Fas-based, inevitably results in target cell apoptotic death.Viral myocarditis has close connection with cytokine. So far TNF-α is well established as inflammatory cytokine involving in myocardial injury. TNF-α can be taken as a good index for clinicians to judge condition and prognosis of children with myocarditis.The pathogenic mechanism is still unclear. Immunopathogensis is taken as a major factor so far. However virus direct effect has close connection with viral myocarditis, especially in acute period, virus duplication is an important reason for myocardial pathology.The incidence of myocarditis increased gradually these years, and fulminant epidemic occured occasionally, especially in newboms, but no effective medicines have been found by now. To explore the effective medicine and the mechanism, Astragalus, traditional Chinese medicine, was selected to research its influence on expression of perform mRNA in myocardium and immunologic injury in mice with acute myocarditis caused by CVB3m.Materials and Methods1. Animal model;24 Balb/c mice 4-6 weeks old were inoculated intraperitoneally with cox-sackievirus B3m and randomly divided into Astragalus treatment group (n = 12) and control group ( n = 12). On half an hour post-inoculation, The mice in two groups were inoculated intraperitoneally with Astragalus injection (lOg/kg d) and sterilized water respectively once a day for 7 days. Heart and blood samples were obtained from all mice on the 8th day after CVB3minfection for hispathologi-cal and ultrastructural study, detection of myocardial perform, FasL and CVB3m expression by reverse transcription-polymerase chain reaction ( RT-PCR) and measurement of serum CK-MB, TNF-α level, respectively.2. Major instruments and reagents Instruments1) Olympus microscope2) 1200 EX transmission electron microscope3) LKB-V ultramicrotome4) PCR analyzer (PE-9600 made in USA)5) Kodak image analysis system6) HITACHI 7170 automatic analyzer Reagents1) TRIZOL reagent of total RNAs came from promega . p-αctin was taken as internal control.2) Astragalus injection, 2g/ml, made in Shanghai Fuda Pharmaceutical CO. LTD. Number; 0006173) TNF-α radioimmunology kit3. Methods1) Myocardial hispathological studyThe fixed samples were studied after dehydration, inwax, cutting, and HE staining by microscope to observe hispathological changes of myocardium and take pictures.2) Myocardial ultrastructural studyHeart tissues were fixed with 2. 5% Glutaradehyde and 1% Osmic acid, dehydrated with serial alcohol, embedded with E-pon 812 resin, an...
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