Synthesis of squalene and sterols by isolated segments of human and pigeon arteries

Abstract

The ability of isolated arterial segments from man and pigeon to synthesize squalene and sterols from dl-mevalonate-2-14C has been studied by an in vitro perfusion technique. Following a 4-hour perfusion, more than 99% of the lipid radioactivity was contained in two major fractions after chromatography on alumina. The less polar fraction, accounting for 30-60% of the total lipid radioactivity in arterial segments from pigeon and man respectively, was shown to be more than 95% squalene. Squalene synthesis in the pigeon was positively and significantly correlated with the severity of atherosclerosis. Because of the highly variable postmortem interval, no such correlation was attempted for human arterial segments. The polar fraction from the alumina column, although possessing properties similar to cholesterol, contained on the order of 1% cholesterol when purified through the dibromide. The identity of the major portion of radioactivity in this fraction remains unknown. © 1968.