Tu Y P, Xu H, Yang F Y
National Laboratory of Biomacromolecules, Academia Sinica, Beijing, China.
Biochem Mol Biol Int. 1994 Jun;33(3):597-605.
Sarcoplasmic reticulum (SR) vesicles with (1000 folds) or without transmembrane Ca2+ gradient have been prepared. Different fluorescence probes (DPH, TMA-DPH and n-AS), were used to determine the effect of transmembrane Ca2+ gradient on the lipid fluidity both in outer and inner layer of Ca(2+)-ATPase-containing SR vesicles. The results showed that transmembrane Ca2+ gradient could significantly decrease the fluidity of the inner layer of SR membrane, while no obvious change was monitored in the outer layer. This may be deduced that Ca(2+)-ATPase might be modulated mainly by the transmembrane Ca2+ gradient-mediated alteration of physical state of phospholipid in the inner layer of SR membrane.
已制备出具有（1000倍）或不具有跨膜Ca2+梯度的肌浆网（SR）囊泡。使用不同的荧光探针（DPH、TMA-DPH和n-AS）来测定跨膜Ca2+梯度对含Ca(2+)-ATP酶的SR囊泡外层和内层脂质流动性的影响。结果表明，跨膜Ca2+梯度可显著降低SR膜内层的流动性，而外层未监测到明显变化。由此可以推断，Ca(2+)-ATP酶可能主要受跨膜Ca2+梯度介导的SR膜内层磷脂物理状态改变的调节。
