Long-lived labeling of phagocytic cells with analogs of atheroma lipids.

[3H]Trioleyl glyceryl ether and [3H]cholesteryl linoleyl ether were bound to Intralipid and injected intraperitoneally into mice. About 20% of the injected label was recovered from peritoneal macrophages up to 2 weeks after injection, and there was a gradual appearance of the label in the liver. Following injection of acetylated low density lipoprotein, labeled with [3H]trioleyl glyceryl ether, into rats, about 90% of the label appeared in the liver shortly after injection and all label was retained up to 73 days. The findings indicate that [3H]cholesteryl linoleyl ether and [3H]trioleyl glycerol can serve as non-degradable analogs of atheroma lipids, which are readily taken up by macrophages when presented in the form of appropriate substrates. These preliminary results serve as basis for experiments designed to study the role of macrophages in the transport of atheroma lipids.