Preferential binding of [3H]cholesteryl linoleyl ether-HDL3 by bovine adrenal membranes

Membranes isolated from bovine adrenal cortex, incubated with human high-density lipoproteins (HDL3), labeled with 125I and [3H]cholesteryl linoleyl ether, showed preferential binding of [3H]cholesteryl linoleyl ether. The preferential binding was Ca2+ independent, temperature sensitive and was slightly increased after phospholipase C or pronase treatment. Reduction of membrane phosphatidylcholine by phospholipase A2 resulted in a marked increase in the binding of the entire HDL3 particle and a relative decrease in preferential binding of [3H]cholesteryl linoleyl ether. These findings suggest that the presence of intact phospholipid in the membrane plays an important role in the magnitude of the preferential binding.