THE BINDING OF TRIETHYLTIN TO RAT BRAIN MYELIN

—A high affinity binding site for triethyltin was found in rat brain myelin with an affinity of approx 6·6 × 10⁵m ⁻¹ at pH 7·5. Competitive binding studies showed that triethyl-lcad had about the same affinity and trimethyltin 30 times lower affinity than triethyltin. Hexachlorophane and 3,5-diiodo-4′-chlorosalicylanilide did not prevent triethyltin binding to rat brain myelin. Since triethyltin, hexachlorophane and 3,5-diiodo-4′-chlorosalicylanilide all produce similar oedematous lesions in the brain of rats, whereas triethyl-lead and trimethyltin do not, it is concluded that the high affinity triethyltin binding site either is not involved or is not the only factor in oedema production.