[Tetracycline antibiotic interaction with the subcellular fractions of rat liver homogenate].

Binding of tetracyclines, i. e. tetracycline, oxytetracycline, morphocycline, methacycline and doxycycline by subcellular fractions of rat liver homogenates was studied on randombred albino rats. It was shown that the drugs lost their activity to a significant extent on contact with nuclei, mitochondria, microsomes and the fraction mixtures. The mitochondrial fraction bound the highest amounts of the drugs. The binding level of methacycline by the organoids was the highest, while that of morphocycline was the least. Binding of the tetracyclines with the subcellular fractions of the liver was to a certain extent reversible. Accumulation of the antibiotic in the cells may be advantageous from the viewpoint of its effect on the intracellular microbes if possible subsequent dissociation from its complex with organoids is considered. At the same time the mitochondriatropic properties of the tetracyclines may be the basis for their toxic effect on the host cells.