Influence of a Chinese crude drug on Ca2+ influx and efflux in rat visceral organs: investigation and evaluation by 45Ca.

The influences of a Chinese crude drug, Herba Epimedii, (HE), on Ca2+ influx and efflux in the isolated rat aorta and some visceral organs were evaluated by using 45Ca as a radioactive tracer. Additionally, its protective effect on myocardial ischemia was investigated in live animals. The results indicated that HE has significant influence on Ca2+ influx and efflux in the isolated rat aorta, heart, and kidney, in that it can markedly block 45Ca entering into cell and can facilitate efflux of intracellular Ca2+. However, among the three kinds of extracts from HE, the alkali extracts have the most obvious effect on calcium channels in visceral organs. Even if the alkali extracts are diluted by water for 10 times, the material still has a rather strong inhibition effect on calcium channels. Fortunately, the three kinds of extracts have favorable protective effect on myocardial ischemia induced by drugs or by the ligation of the coronary artery. This is consistent with the results about the Ca2+ influx and efflux obtained by isotope tracer technique, and implies that the Chinese crude drug has attractive potential for the treatment of heart, cerebrovascular and other diseases.