[ 125I]LDL uptake in rabbit arteries perfused in situ effect of HDL on intact and de-endothelialized vessels

The uptake of [ 125I]LDL by rabbit abdominal and thoracic aortae, and carotid arteries perfused in situ was studied. [ 125I]LDL uptake in vessels with intact endothelial covering was saturable, Ca 2+,Mg 2+-dependent and was inhibited by a 100-fold excess of LDL and HDL, on the average by 30% and 60%, respectively. In de-endothelialized vessels [ 125I]LDL uptake increased by approximately 3-fold, and was not reduced in the presence of excess of unlabeled LDL and HDL.