Altered membrane anisotropy gradients of plasma membranes of living peripheral blood leukocytes in aging and Alzheimer's disease.
Several reports have suggested that membrane rigidity, a term that refers to the relative motion of membrane constituents, is decreased in Alzheimer's Disease. Accordingly, a series of fluorescent membrane probes was used to evaluate the rigidity from the surface to the center of the outer hemi-leaflet of the plasma membrane of living neutrophils, monocytes and lymphocytes. Anisotropy, a parameter which increases with increasing membrane rigidity, was calculated from flow cytometric measurements of vertically and horizontally polarized components of the fluorescence emission of the probes. These preliminary experiments suggest that whereas membrane rigidity in certain regions of the plasma membrane of peripheral blood leukocytes is increased as expected in elderly controls, it is decreased in Alzheimer's disease.
Collins
J M
JM
Department of Biochemistry and Molecular Biophysics, Medical College, Virginia Commonwealth University, Richmond 23298.
Scott
R B
RB
McClish
D K
DK
Taylor
J R
JR
Grogan
W M
WM
D000375:Aging / Q000097:blood*; D000544:Alzheimer Disease / Q000097:blood*; D002462:Cell Membrane / Q000378:metabolism; D004161:Diphenylhexatriene / Q000031:analogs & derivatives; D005454:Fluorescence Polarization; D005456:Fluorescent Dyes; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D008560:Membrane Fluidity; D015335:Molecular Probes
D005456:Fluorescent Dyes; D015335:Molecular Probes; D004161:Diphenylhexatriene; C033628:1-(4-(trimethylamino)phenyl)-6-phenylhexa-1,3,5-triene