[Oxidative phosphorylation uncoupling in hyperthyroidism as a result of activating cyclosporin-sensitive pores in the inner mitochondrial membrane by water soluble modulators from rat liver cytoplasm].

Small concentrations of low molecular weight modulators of the functional state of rat liver cytoplasm mitochondria, which uncouple oxidative phosphorylation, induce phosphate-dependent transport of potassium and hydrogen ions. In contrast, high concentrations of these compounds induce nonspecific transport of monovalent cations and sucrose (K+ > H+ > Na+ > or = Li+ > sucrose). The effect of cytoplasmic modulators on oxidative phosphorylation and permeability of the inner mitochondrial membrane in inhibited by cyclosporin A and controlled by physiological concentrations of Ca2+. It is assumed that ion transport across the inner mitochondrial membrane in the presence of cytoplasmic modulators is implemented by the same cyclosporin-sensitive transport system which in damaged mitochondria functions as a nonspecific pore.