Changes in lipid content and composition during the development of N-nitrosodiethylamine induced hepatocarcinoma.
Alterations in lipid content and composition in the N-nitrosodiethylamine-induced hepatocarcinoma were investigated. Rats were administered with N-nitrosodiethylamine in the drinking water for 12 weeks followed by normal tap water for another 6 weeks. The cholesterol content in the liver was increased shortly after the administration of N-nitrosodiethylamine and remained elevated after the removal of the nitrosoamine from the water. The phosphatidylethanolamine level was elevated during N-nitrosodiethylamine administration with a concomitant reduction in phosphatidylcholine level. Lysophosphatidylcholine and sphingomyelin levels were increased during the last four weeks of the study. The level of phosphatidylinositol was substantially reduced after eight weeks of N-nitrosodiethylamine treatment, and remained low during the post-treatment period. We postulate that changes in lysophosphatidylcholine and sphingomyelin may be a compensatory mechanism for maintaining the asymmetrical distribution of choline-containing lipids in the outer leaflet of the membrane. The elevated level of cholesterol may be a useful indicator for the early detection of N-nitrosodiethylamine-induced hepatocarcinoma.
Tang
H
H
Department of Biochemistry, Shanghai Medical University, People's Republic of China.
Choy
P C
PC
Chen
H
H
D000818:Animals; D002784:Cholesterol / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004052:Diethylnitrosamine; D050356:Lipid Metabolism; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced / Q000378:metabolism*; D008297:Male; D008563:Membrane Lipids / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D008563:Membrane Lipids; D010743:Phospholipids; D011506:Proteins; D004052:Diethylnitrosamine; D004247:DNA; D002784:Cholesterol