Cocaine-like action of diphenhydramine in cat cerebral arteries.

Diphenhydramine (5.3 X 10(-7) M) significantly reduced the tritium efflux evoked by 10(-7) M tyramine from cat cerebral arteries preloaded with [3H]noradrenaline but not that brought about by 50 mM KCl. These results indicate the ability of diphenhydramine to block the amine neuronal uptake.