Tri-n-butyltin Aggregates and Membrane Cytotoxicity in Human Erythrocytes

Abstract

Tri-n-butyltin (TBT) compounds are potent membrane effectors and their biological effects are due primarily to membrane perturbations. One tenth <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">\mu</tex> M TBT induces reversible discocyte-to-echinocyte transformations in human erythrocytes. TBT concentrations <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">\geq 1.0 \mu</tex> M cause irreversible erythrocyte shape transformations and TBT <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">\geq 5 \mu</tex> M induces hemolysis. NaCN synergistically stimulates TBT mediated hemolysis. Human erythrocytes exposed to TBT <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">\geq 10 \mu</tex> M have membrane associated tin containing aggregates intercalated between the inner and outer membrane leaflets . Tripropyltin, tetrabutyltin, and triethyltin compounds also form electron microscopically visible membrane aggregates. In addition, select dimercapto compounds inhibit TBT mediated hemolysis implicating their possible use as therapeutic agents.