Effects of Ro 11-2465, a new psychotropic agent on the uptake of serotonin by human platelets--in vitro determination of the IC50.

The influence of Ro 11-2465, a new psychotropic agent, on the in vitro uptake of 3H-serotonin into human blood platelets was studied and compared with that of clomipramine, imipramine and amitriptyline. These compounds inhibited the uptake of serotonin in a dose-dependent manner. Ro 11-2465 was found to be six times more potent than clomipramine and 14 times more potent than imipramine in its ability to inhibit serotonin uptake. IC50 value determined for Ro 11-2465 was 7 x 10(-10) M. The results indicate the potential ability of Ro 11-2465 to interfere with the human serotoninergic mechanism.