[Transformation of mouse peritoneal macrophages to foam cells in intraperitoneal injection of low density lipoproteins, cholesterol and its oxidized products].

To investigate the possibility of macrophage transformation to foam cells in vivo, the authors studied 14C-oleate incorporation into cellular cholesterol esters (CES) and the content of free cholesterol (CS) and CES in mouse peritoneal macrophages harvested 24 hours after intraperitoneal injection of native low density lipoproteins (LDL), acetylated LDL (acetyl-LDL), purified CS and CS autooxidated at 60 degrees C for a month. The rate of 14C-oleate incorporation into CES and the content of CES in the macrophages increased in relation to CS levels in the preparations and the nature of the injected agents. Injection of acetyl-LDL (2 mg CS/18 g body weight) and oxidized CS (1 mg/18 g body weight) caused a 10-fold increase of 14C-oleate incorporation into CES and a 60-fold increase of CES concentrations in the macrophages, which was evidence of their transformation to foam cells. The model of obtaining foam cells in vivo may be used in the study of atherogenesis.