title: Age-related changes in rat liver plasma membrane phospholipase A2 activity.
abstract: The alterations of the lipid composition and fluidity of liver plasma membranes as well as the activity of membrane-bound phospholipase A2 (EC 3.1.1.4) in male and female rats of different ages are investigated. An age-induced increase of the protein/phospholipid and cholesterol/phospholipid ratios is observed, as well as a decrease in the unsaturation index of plasma membrane phosphatidylcholine. These changes induce an augmentation of the steady-state fluorescent anisotropy-rs and structural order parameter for 1,6-diphenyl-1,3,5-hexatriene-SDPH in plasma membranes. The membrane-bound phospholipase A2 activity is enhanced with aging, correlating well with the reduced membrane fluidity. The sex-determined alterations in all these parameters is also investigated.
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D002784:Cholesterol / Q000032:analysis; D005260:Female; D008099:Liver / Q000032:analysis / Q000201:enzymology*; D008297:Male; D008560:Membrane Fluidity; D008563:Membrane Lipids / Q000032:analysis; D010740:Phospholipases / Q000378:metabolism*; D010741:Phospholipases A / Q000378:metabolism*; D054467:Phospholipases A2; D051381:Rats; D012737:Sex Factors
chemical_list: D008563:Membrane Lipids; D002784:Cholesterol; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2