Oxidative phosphorylation. Biochemical effects and properties of trialkyltins

Abstract

Trimethyl-, triethyl-, tri-n-propyl- and tri-n-butyl-tin stimulate adenosine-triphosphatase activity and cause limited swelling of rat-liver mitochondria. These two effects occur at the same concentration of a particular trialkyltin. The level of the adenosine-triphosphatase activity induced varies with each trialkyltin and is only 17-40% of that produced by 30 [mu]M-2,4-dinitrophenol. Nevertheless, both stimulation of adenosine-triphosphatase activity and inhibition of oxidative phosphorylation occur at the same concentration of a particular trialkyltin. Triethyltin inhibits the shrinking by ATP of mitochondria swollen by treatment with inorganic phosphate or L-thyroxine. Triethyltin has affinity for substances that are lipophilic and are negatively charged. The hypothesis that combination of trialkyltins with negatively changed lipids is involved in their biological action is discussed.