Effects of hydrophobicity on turnover of plasma high density lipoproteins labeled with phosphatidylcholine ethers in the rat.
Rat high density lipoproteins (HDL) were labeled with a series of phosphatidylcholines and ether analogs of phosphatidylcholine. The rates of turnover of the phosphatidylcholine ethers in the rat decreased as a function of increasing hydrophobicity and were more than five times faster than those of apolipoprotein A-I turnover and spontaneous lipid transfer. The major tissue sites for uptake were the liver, adrenals, and ovaries. The rate of turnover of a phosphatidylcholine was faster than that of the corresponding ether analog due to the action of lecithin:cholesterol acyltransferase, although this activity was slow compared to the turnover of high density lipoprotein-phosphatidylcholine. Injection of a purified human phosphatidylcholine transfer protein increased the turnover rate of a phosphatidylcholine and its ether analog. We conclude that a major route for the turnover of plasma high density lipoprotein-phosphatidylcholine in the rat is independent of spontaneous lipid transfer, hydrolysis, and HDL particle uptake, and that it involves the activity of a plasma phosphatidylcholine transfer protein.
Pownall
H J
HJ
Department of Medicine, Baylor College of Medicine, Houston, TX.
Hickson-Bick
D
D
Massey
J B
JB
D000818:Animals; D002850:Chromatography, Gel; D005260:Female; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood* / Q000737:chemistry; D009928:Organ Specificity; D010713:Phosphatidylcholines / Q000097:blood*; D010742:Phospholipid Ethers / Q000097:blood; D051381:Rats; D011919:Rats, Inbred Strains; D014867:Water / Q000737:chemistry
D008075:Lipoproteins, HDL; D010713:Phosphatidylcholines; D010742:Phospholipid Ethers; D014867:Water