Binding of N-(2-bromo ethyl)-N-ethyl-N 1 -naphthylmethylamine HBr (SY28) to the proteins of guinea-pig vas deferens.

1. Vasa deferentia from guinea-pigs were exposed to (14)C-SY28 HBr (5.32 x 10(-6)M) washed, lipid extracted, and broken up.2. The tissue was digested with papain, hydrolyzed with 6 N HCl, and gel filtration performed.3. Aliquots at each stage were used for paper chromatography and autoradiography.4. Three labelled spots (in addition to unbound 2-halogenoalkylamine) were located from acid hydrolysate and a fourth from gel filtrate.5. Selected amino-acids were complexed with (14)C-SY28 and the procedure repeated. The R(F) values were compared with those of the same amino-acids with and without 6 N HCl.6. Histidine, aspartic acid, arginine and serine gave a significant degree of binding of (14)C-SY28.7. The theoretical implications are discussed.