Mg2＋对阿霉素引起心肌线粒体F1F0变化的保护

抗肿瘤药物阿霉素(ADM)对心肌线粒体F₁F₀-复合体呈现抑制而对F₁-ATPase无抑制,这表明ADM可能是通过膜脂起作用的,适当浓度Mg²⁺能降低ADM对复合体的抑制.经 ³¹P-NMR和标记荧光探针NBD-PE,DPH,MC-540以及内源荧光等的测定,结果表明ADM可能首先通过诱导F₁F₀膜脂形成非双层脂结构,继而影响了膜脂的堆积程度和流动性,进而引起F₁F₀-复合体酶蛋白构象的改变,最终导致酶活力的降低.Mg^2＋则可能由于与ADM竞争与心磷脂的结合,而对ADM引起F₁F₀的变化产生保护作用.

The Protecting Effect of Mg on the Changes of Cardiac Mitochondrial FF Induced by Adriamycin

Adriamycin (ADM) is a widely used anticancer drug, but the chronic cardiotoxicity severely limits the use of it in the treatment of neoplastic disease. The experimental results obtained from F₁F₀-ATPase activity assay. ³¹P-NMR spectra measurement. fluorescent probe NBDPE detection. packing and fluidity of membrane lipids and intrinsic fluorescence measurements can be summarized as follows: ADM induces the phase transition of mitochondrial membrane lipids at first. as a consequence affecting on the lipid packing and fluidity of the lipid molecules and then influencing the conformation of the F₁F₀-ATPase and finally resuiting in the decreasing of the enzymatic activity. And Mg²⁺ can protect all the effects induced by ADM thus reducing the harmful effect of ADM.