Photoaffinity labelling of the serotonin carrier protein in platelets and brain synaptosomes

Azidoimipramine, a photoaffinity labelling reagent for the serotonin transport protein, was synthesized. This reagent, upon irradiation, binds covalently to brain synaptosomes preparation and to gel-filtered platelets. Two-dimensional SDS-polyacrylamide gel electrophoresis-isoelectric focusing and tritium fluorography analysis indicate that two synaptosomal proteins and four platelets proteins were labelled by [3H]azidoimipramine.