Toxicity of organotin compounds for polymorphonuclear leukocytes: The effect on phagocytosis and exocytosis

Abstract

Phagocytosis and concomitant release of enzymes by rabbit polymorphonuclear leukocytes (PMNs) are inhibited by micromolar concentrations of triphenyltin and tributylin; inhibition by triethylin occurs at higher concentrations. Chemotactic peptide-induced exocytosis is inhibited at the same concentrations as phagocytosis. Tributylin causes cell lysis at slightly higher concentrations as required for inhibition of phagocytosis and exocytosis. The organotin compounds have little effect on ATP level in PMNs, which makes an effect on metabolic energy providing processes unlikely. The increase of Ca2+-permeability of the plasma membrane, induced by chemotactic peptide, is inhibited by the organotin compounds. Inhibition of exocytosis by triphenyltin can be counteracted by a number of sulfhydryl compounds. The results suggest that the organotin compounds interfere with PMN function in an early phase of cell activation, where all functions have a common pathway, and where vulnerable sulfhydryl groups play a pivotal role.