Study On The Effect Of Total Saponins Of Panax Notoginseng And Ligustrazine On Myocardial Calcium Overload In The Mice With Viral Myocarditis

Viral myocarditis(VMC) is one of the common cardiovascular diseases in pediatrics. Since the 1970's, the occurrence of viral myocarditis has become more and more, and there have been many reports on the clinical data and virological diagnosis of it. However, its pathogenesis has not clarificated completely, thus, later on, the focus of research of all countries shifted to its pathogenesis. In recent years, along with the rapid development of molecular biology, the research on this disease has had some great breakthroughs, but no therapy with obvious effect has been found out yet. The way to deal with it is still mainly the specific treatment of specific symptoms. Along with the deep going of the research on the disease, the integrated traditional Chinese and western medicine has produced obvious effects, showing a good prospect of the treatment of viral myocarditis.The experimental study on the mouse acute VMC induced with Coxsackie virus B(CVB) has shown that there are at least two kinds of mechanism of myocardial damage related to virus infection. One is the direct damaging action of the virus, and the other is the damaging effect of the immunoreaction of the body on the myocardial cells. Research has shown that, both the direct action of the virus and the immunologic injury can lead to the overload of the myocardial intracellular Ca2+ and the calcium overload is also a pathogenesis for the myocardial damage of VMC. Another conclusion is that calcium overload is one of the common way for the damage and necrosis of myocardial cells. The chief physiological function of the sarcoplasmic reticulum (SR) of the myocardial cell is to adjust the concentration of calcium ions in the myocardial cell so as to control the contraction and diastole of the cardiac muscle. Research has found out that, 90% of the increase of the concentration of free calcium ions in the myocardial cell is a result of the releasefrom the SR, while the 70% - 75% of the decrease of the concentration of free calcium ions during the phase of relaxation is a result of the fact that the SERCA2a has taken them in and stored them in the sarcoplasmic reticulum. If the structure and function of SR have become abnormal , abnomal metabolism of calcium ions will be caused, which will easily result in insufficiency of diastole and contraction of cardiac muscles, even causing the heart failure.Total Saponins of Panax Notoginseng (TSPNS) is a commonly used traditional Chinese medicine. It is composed of the major active ingredients of panax notoginseng, chiefly being Rb1 and Rg1. Both Rb1 and Rg1 have an inhibiting action on the motion of calcium ions: the function of Rb1 is to prevent the calcium ions entering cell from outside while that of Rg1 is to inhibit the release of intracellular calcium ions. As Rb1 and Rg1 function in different steps of the motion of the calcium, the two may have a synergetic function together. A lot of research on pharmacology has shown that, TSPNS is able to inhibit platelet aggregation, resist thrombosis, increase coronary flow, lower blood pressure and produce the negative inotropic action of the cardiac muscles, thus, it can serve as a remedy for the energy deficiency of the cardiac muscle. Research results have proved that, through the above- mentioned many pharmacological actions, TSPNS has enhanced the activity of the calcium pump on the myocardial cell membrane, greatly relieving the overload of the myocardial intrallular Ca2+.Ligustrazine is the effective ingredient of the Chinese traditional medicine, chuanxiong rhizome, extracted from the latter. It is an alkaloid, whose major function is promoting blood circulation and removing blood stasis. In the earlier time, it was mostly studied and used from the function of promoting blood circulation and removing blood stasis. But with the deep going of the research, we have found many more functions of it, thus, its scope of clinical application is gradually expanding as well. At present, ligustrazine has become a commonly used and safe medicine for clinical treat...