粉防己碱对离体大鼠心脏钙反常的保护作用

粉防己碱(Tet)能明显抑制离体大鼠心脏钙反常时心肌组织LDH和蛋白的释出,减少无钙灌流时心肌组织Ca²⁺丢失和Na⁺堆积以及复钙灌流时心肌组织Ca²⁺,Na⁺堆积和Mg²⁺,K⁺丢失,并呈浓度依赖性。此外,钙反常时心肌组织中微量元素Fe,Zn含量下降,Cu含量增加,而Tet可抑制Fe及Zn含量的下降。维拉帕米(Ver)也有类似作用,电镜下,Tet可部分减轻钙反常时心肌组织超微结构的破坏。

PROTECTIVE EFFECTS OF TETRANDRINE ON CALCIUM PARADOX IN ISOLATED RAT HEART

The protective effects of tetrandrine (Tet) on calcium paradox in isolated Langendorffs heart in rats were investigated. Tet was shown to reduce the release of lactate dehydrogenase (LDH) and protein from myocardial tissues and the loss of K⁺, Mg²⁺ and accumulation of Ca²⁺, Na⁺ in myocardial tissues during calcium paradox in a concentration—dependent manner. Decrease of Fe and Zn and increase of Cu in myocardial tissues were observed in calcium Paradox and Tet 27 μmol/L was found to inhibit the decrease of Fe and Zn. In addition, Tet was also found to inhibit the decrease of Ca²⁺ and the increase of Na~+ in myocardial tissues during calcium—free perfusion. These results indicate that Tet can protect the myocardium against calcium paradox by stabilizing cellular membrane and inhibiting the influx of Ca²⁺.