Lipid fluidity and composition of the erythrocyte membrane from healthy dogs and Labrador retrievers with hereditary muscular dystrophy.
Erythrocyte membranes and their liposomes were prepared from clinically normal dogs and Labrador retrievers with hereditary muscular dystrophy. The "static" and "dynamic" components of fluidity of each membrane were then assessed by steady-state fluorescence polarization techniques using limiting hindered fluorescence anisotropy and order parameter values of 1,6-diphenyl-1,3,5-hexatriene (DPH) and fluorescence anisotropy values of DL-2-(9-anthroyl)-stearic acid and DL-12-(9-anthroyl)-stearic acid, respectively. Membrane lipids were extracted and analyzed by thin-layer chromatography and gas chromatography. The results of these studies demonstrated that the lipid fluidity of erythrocyte membranes, and their liposomes, prepared from dystrophic dogs were found to possess significantly lower "static and dynamic components of fluidity" than control counterparts. Analysis of the composition of membranes from dystrophic dogs revealed a higher ratio of saturated fatty acyl chain/unsaturated chains (w/w) and lower double-bond index. Alterations in the fatty acid composition such as decrease in levels of linoleic (18:2) and arachidonic (20:4) acids and increase in palmitic (16:0) and stearic (18:0) acids were also observed in the membranes of dystrophic animals. These associated fatty acyl alterations could explain, at least in part, the differences in membrane fluidity between dystrophic and control dogs.
Mehta
J R
JR
Neuromuscular Laboratories of Scott-Ritchey Research Program, College of Veterinary Medicine, Auburn University, AL 36849.
Braund
K G
KG
Hegreberg
G A
GA
Thukral
V
V
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000097:blood; D004161:Diphenylhexatriene; D004285:Dogs; D004910:Erythrocyte Membrane / Q000502:physiology*; D005454:Fluorescence Polarization; D005456:Fluorescent Dyes; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000097:blood; D008560:Membrane Fluidity; D008563:Membrane Lipids / Q000097:blood; D009137:Muscular Dystrophy, Animal / Q000097:blood*; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000097:blood; D013229:Stearic Acids / Q000097:blood
D001095:Arachidonic Acids; D005456:Fluorescent Dyes; D008041:Linoleic Acids; D008563:Membrane Lipids; D010169:Palmitic Acids; D013229:Stearic Acids; D004161:Diphenylhexatriene; D016718:Arachidonic Acid; D019308:Palmitic Acid; C030310:12-(9-anthroyl)stearic acid; C031183:stearic acid; D019787:Linoleic Acid