INHIBITION OF CHOLESTEROL BIOSYNTHESIS BY A MITOCHONDRIAL EXTRACT

Abstract

Cholesterol biosynthesis was effectively inhibited by an extract of mitochondria disrupted with sonic oscillations. The inhibitory effect occurred both in vivo and in vitro. The inhibitor substance was heat-labile, and could be prepared from mitochondria from livers of normal or starved rats. The inhibition appeared to be of the competitive type. The locus of the inhibition in the chain of reactions from acetate to cholesterol appeared to be between acetoacetate and mevalonate. It is suggested that the inhibitor substance present in the mitochondrion represents, in part, the homeostatic mechanism that controls cholesterol synthesis by the liver.