VLDL is 30-80nm in size and contains triglycerides, cholesterol, cholesterol esters and phospholipids, in which triglycerides (TG) account for 60%, cholesterol (TC) accounts for 20%, apolipoprotein accounts for 65,438+00% and other components account for 65,438+00%. Protein consists of ApoA, Aⅳ, B 100, c, e, etc.
VLDL is synthesized in the liver, using fatty acids from lipid pool as synthetic raw materials, in which cholesterol comes from CM residues and the part synthesized by the liver itself. ApoB 100 is all synthesized by liver. The VLDL synthesized by the liver is secreted and enters the blood through veins, then LPL is activated by ApoC in VLDL, and TG in VLDL is hydrolyzed. Hdlcat action produced
Cholesterol esters are transferred to VLDL through CETP for exchange, while the remaining phospholipids, ApoE and C in VLDL are transferred to HDL, and VLDL is converted into VLDL residues, and then most of them are ingested into the liver through VLDL receptors, and a small part is converted into LDL for further metabolism.
Extended data
function
Liver cells can synthesize triglycerides from glucose or fatty acids mobilized by food and adipose tissue, and then combine with apolipoprotein B 100, apolipoprotein E, phospholipids and cholesterol to form very low density lipoprotein.
In a low-fat diet, intestinal mucosa can also secrete some very low-density lipoprotein into the blood. After very low density lipoprotein enters the blood, most of it becomes low density lipoprotein.
Due to the slow metabolism of very low density lipoprotein in blood, the half-life is 6 ~ 12 hours, so there is still a certain amount of very low density lipoprotein in fasting blood. Very low density lipoprotein (VLDL) is not easy to penetrate the intima of artery because of its relatively small cholesterol and relatively large particles.
Baidu encyclopedia-very low density lipoprotein