Evaluation of membrane fluidity in cerebral microvasculature.
Cerebromicrovascular membrane fluidity was studied in two model systems: 1) hepatic encephalopathy and 2) cultured endothelium exposed to free arachidonic acid alone or with H2O2. The membrane fluidity was measured by fluorescence anisotropy using 1, 6-diphenyl-1,3,5-hexatriene as a fluorescent probe. In addition, the effect of arachidonic acid with or without H2O2 on cellular permeability to trypan blue-albumin was investigated in endothelial cultures. The findings indicate that the hepatic encephalopathy and the arachidonic acid treatment of endothelium causes an increase in membrane fluidity. This modulation of endothelial membrane fluidity is not associated with changes in cellular permeability to trypan blue-albumin complex. An increased cellular permeability to trypan blue-albumin complex was seen after endothelial exposure to arachidonic acid and H2O2.
Villacara
A
A
Laboratory of Neuropathology and Neuroanatomical Sciences, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892.
Zanchin
G
G
Spatz
M
M
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology; D001921:Brain / Q000098:blood supply*; D002463:Cell Membrane Permeability / Q000502:physiology; D002478:Cells, Cultured; D004161:Diphenylhexatriene; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects; D006501:Hepatic Encephalopathy / Q000503:physiopathology; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008560:Membrane Fluidity / Q000502:physiology; D008833:Microcirculation; D051381:Rats
D001095:Arachidonic Acids; D004161:Diphenylhexatriene; D016718:Arachidonic Acid; D006861:Hydrogen Peroxide