Effect of long-term aluminum feeding on lipid/phospholipid profiles of rat brain myelin.

Effect of long-term (90-100 days) exposure of rats to soluble salt of aluminum (AlCl3) on myelin lipid profile was examined. The long-term exposure to AlCl3 resulted in a 60% decrease in the total phospholipid (TPL) content while the cholesterol (CHL) content increased by 55%. Consequently the TPL/CHL molar ratio decreased significantly by 62%. The phospholipid composition of the myelin membrane changed drastically; the proportion of practically all the phospholipid classes decreased by 32 to 60% except for phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Of the latter two, proportion of PC was unchanged while PE increased in proportion by 47%. Quantitatively, all phospholipid classes decreased by from 42 to 76% with no change in the PE content. However the membrane fluidity was not altered in Al-treated rats. Many of the changes we observe here show striking similarities with the reported phospholipid profiles of Alzheimer brains.