铅对离体大鼠肾微粒体膜流动性和膜表面负电荷密度的影响

Effects of Pb^(2+) on Membrane Fluidity and Surface Negative Chargy Density of Rat Renal Microsome in vitro

本研究观察了的Pb^(2+)对大鼠肾微粒体膜物理状态的影响。结果表明,Pb^(2+)能明显增加ANS与膜结合后的荧光强度和荧光偏振度,但不改变荧光光谱特性。用ANS荧光滴定法研究发现,Pb^(2+)能降低膜ANS复合物的表观解离常数和增加膜上ANS的结合位点数。提示,Pb^(2+)能降低离体大鼠肾微粒体膜流动性和膜表面负电荷密度。

The effects of Pb2+ on Physical state of membrane of rat renal microsome were observed using ANS as a fluorescence probe. The results showed that Pb2+ significantly increased fluorescence intensity and Polarization of ANS bound to the membranes, but no change was observed in the property of fluorescence spectra.By means of the titration of the membrane with ANS, it was found that Pb2+ decreased the apparent dissociation constant of ANS membrane complex and enhanced number of the ANS binding site in the membrane. These results suggest that Pb2+ decrease the membranes fluidity and surface negative charge density of rat renal microsome.