Influence of chlorpromazine on the accumulation of 5-hydroxytryptamine by interaction with ATP

5-Hydroxytryptamine accumulates at pH 6.0 when ATP is present on one side of an artificial lipoidal barrier. In the presence of chlorpromazine, the diffusion of ATP through the barrier and a decrease in the accumulation of serotonin can be noted. The diffusion rate constants of ATP and serotonin are related to the concentration of chlorpromazine.