The effect of fibrillar A Beta 1-40 on membrane fluidity and permeability.
The time course of A beta fibril formation was characterized using a variety of assays. The effect of A beta on the membrane fluidity and permeability was assessed by monitoring the anisotropy of the fluorescent probe DPH and TMA-DPH and measuring the release of vesicle-entrapped with three different molecular weight fluorescence probes (ANTS/DPX, Calcein, FD-4). The results show fibrils had formed after 4 days. Aggregated A beta may decrease the membrane fluidity and induce the leakage of ANTS and Calcein in a dose  dependent manner. These effects may have some relation with A beta neurotoxicity.
Department of Biophysics, School of Basic Medical Sciences, Peking University, Beijing 100083, PR China.
Ma
M
Xiaocui
Yinlin
Y
Sha
Kechun
K
Lin
Songqing
S
Nie
D016229:Amyloid beta-Peptides / Q000737:chemistry*; D016880:Anisotropy; D002462:Cell Membrane / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008027:Light; D008081:Liposomes; D008854:Microscopy, Electron; D010446:Peptide Fragments / Q000737:chemistry*; D012542:Scattering, Radiation; D013050:Spectrometry, Fluorescence; D013997:Time Factors
D016229:Amyloid beta-Peptides; D008081:Liposomes; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40)