Lipid composition of liver plasma membranes from rats intoxicated with carbon tetrachloride.
Rat liver plasma membranes were isolated from rats intoxicated acutely and chronically with carbon tetrachloride and a quantitative analysis of lipids was performed. Membranes from regenerating liver (acute intoxication) are characterized by a 60% drop in total phospholipids with a diminished phosphatidylcholine/phosphatidylethanolamine ratio (PC/PE) and a markedly decreased cholesterol level during the first 3 days after the intoxication, leading to a drastically decreased cholesterol/phospholipid (PL) ratio. In the chronically intoxicated rats (non-regenerating liver), although the phospholipids are diminished, phosphatidylcholine and phosphatidylethanolamine are equally decreased, and therefore the PC/PE ratio is not changed. Cholesterol is not diminished and, since the phospholipids are very low, the ratio cholesterol/PL is increased. These data could be correlated with the membrane fluidity. A decrease in the cholesterol/PL ratio results in a more fluid lipid matrix in the proliferative state of the cell. Treatment with colchicine during chronic intoxication prevented the increase in the cholesterol/PL ratio and improved the clinical conditions of the rats. The modulation of the cholesterol content could be a mechanism to control membrane fluidity during the different physiological states of the cell.
D000818:Animals; D002252:Carbon Tetrachloride Poisoning / Q000473:pathology*; D002462:Cell Membrane / Q000032:analysis*; D002784:Cholesterol / Q000032:analysis; D003720:Densitometry; D008099:Liver / Q000648:ultrastructure*; D008297:Male; D008563:Membrane Lipids / Q000032:analysis*; D010713:Phosphatidylcholines / Q000032:analysis; D010714:Phosphatidylethanolamines / Q000032:analysis; D010743:Phospholipids / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains
D008563:Membrane Lipids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010743:Phospholipids; D002784:Cholesterol