脂肪族类两亲物对肌浆网膜脂区结构的影响

C18饱和脂肪酸和胺可增加DPH标记肌浆网(SR)的荧光偏振度,而C18单不饱和脂肪酸。胺和醇则使其偏振度下降。加入MgATP,可除去单不饱和脂肪胺引起的DPH标记的荧光偏振度下降,并使之高于未加脂肪胺的对照水平。饱和酸及相应胺可使标记于膜脂中层和深层的TAS和12AS的荧光偏振度上升,不饱和酸及相应胺和醇仅使12AS荧光偏振下降。说明脂肪族类两亲物对SR膜流动性的影响与脂肪链饱和程度有关。饱和者主要使膜中、深层流动性下降.不饱和者主要使膜深层流动性升高。

THE EFFECTS OF FATTY AMPHIPHILES ON LIPID DOMAIN STRUCTURE OF SARCOPLASMIC RETICULUM

The degrees of fluorescence polarization, reflecting the motion and fluidity of lipid molecules, of skeletal muscle sarcoplasmic reticulum (SR) labelled with DPH were enhanced by addition of CH saturated fatty acid an;d corresponding amine to the reaction, while those were reduced by cis monounsaturated fatty acid, and corresponding amine and alcohol. The fluorescence polarizations of SR labelled with 7AS and 12AS, probes in the middle and deep layers of membrane lipid, respectively, were also enhanced by the above saturated ones, but only that of 12AS-labelled SR was redduced by the unsaturated ones. It indicated that effects of amphiphiles on SR membrane fluidity depend on the degree of saturation of aliphatic chain. Saturated fatty amphiphiles decreased SR fluidity, mainly in its middle and deep layers, whereas unsaturated ones increased that, specially in the deep layer. Addition of ATP was found to eliminate the decrease of fluorescence polarization in DPH-SR caused by cis-mono-unsaturated amine, and to make it of a higher level than that of control without adding any amphiphiles.