[Structural changes in membrane lipids of the sarcoplasmic reticulum of skeletal muscles during hypercholesterolemia]

Membrane lipid phase has been studied in the sarcoplasmic reticulum (SR) of skeletal muscles, using spin probes. Hypercholesterolemia was found to increase rotation and decrease hydrophobicity of water-soluble probe medium located inside SR vesicles. This is probably indicative of the reduction in SR vesicle membranes. At the same time reduced rotation and increased hydrophobicity and regularity of fat-acid probe micro-environment are observed in hypercholesterolemia, with the differences disappearing nearer to the centre of the membrane. It is suggested that POL activation and cholesterol accumulation in SR membranes in hypercholesterolemia lead to greater density of phospholipid molecules in the membrane.