Effects of ubiquinone and related substances on secretion of aldosterone and cortisol

Abstract
Previous studies had demonstrated the presence of a lipid-soluble factor in pineal extracts which inhibits aldosterone secretion when infused intravenously into intact dogs. Evidence is presented that ubiquinone, a constituent of the lipid fractions, is in large part responsible for this phenomenon. Both isolated and authentic ubiquinone cause significant reductions in aldosterone secretion, while reductions in cortisol secretion are only marginally significant. The reduced (quinol) and the cyclized (ubichromenol) forms were found to be much less active.