Chloride‐Hydroxide Exchange across Mitochondrial, Erythrocyte and Artificial Lipid Membranes Mediated by Trialkyl‐ and Triphenyltin Compounds

Studies of the effects of trimethyltin, tripropyltin, tributyltin and triphenyltin chlorides on the permeability of the inner mitochondrial membrane by the osmotic swelling technique in NaCl and NH 4 Cl media show that these compounds mediate transport of chloride ions. Studies in KCl media show that these compounds mediate a strictly coupled chloride‐hydroxide antiporter transport. This exchange allows rapid titration of mitochondrial contents by pulses of HCl. Similar results on erythrocytes and smectic mesophases indicate that this is a direct action of the tin compounds and is not due to modification of a pre‐existing anion carrier in the membrane.