Anti-imipramine antibodies recognize endogenous serotonin uptake and imipramine binding inhibitors

Calf brain and human platelet extracts purified by Bio-Gel P2 column chromatography contained substances that inhibited serotonin uptake and 3H-imipramine binding. Some of these endogenous substances were also recognized by rabbit antibodies produced against imipramine. The data suggest the possible existence of endogenous serotonin uptake modulators, which may possess a partial molecular structure similar to that identified by the antibodies.