Stimulation of lecithin:cholesterol acyl transfer by intravenous injection of heparin

Intravenous injection of 100 IU heparin per kg body weight caused elevation of the lecithin:cholesterol acyl transfer rate in each one of 11 men, in whom before as well as 5 min and 30 min after heparin application the concentration of unesterified fatty acids in plasma did not reach 0.8 mmol/l. The plasma concentration of unesterified cholesterol in high-density lipoproteins (HDL) increased in parallel at the expense of unesterified cholesterol in very low-density lipoproteins (VLDL) and low-density lipoproteins (LDL). For HDL cholesteryl esters an opposite effect was observed. The results support the hypothesis of a participation of the lecithin:cholesterol acyl transferase (LCAT) in VLDL breakdown.