IN-VITRO AND IN-VIVO EFFECT OF THE NOOTROPIC AGENT ADAFENOXATE ON THE5-HT1 SITES IN DIFFERENT RAT-BRAIN STRUCTURES

1. The effect of the nootropic agent adafenoxate (a structural analogu e of meclofenoxate) on the binding parameters of 5-HT1 receptors in vi tro and in vivo in rat cerebral cortex, striatum, hippocampus and hypo thalamus was studied. 2. The chronic (100 mg/kg per os for 7 days) ada fenoxate treatment produced a significant (24.6%) decrease in the dens ity of 5-HT1 sites in the hippocampus.3. In vitro adafenoxate inhibite d specific [H-3]5-HT binding with equal potency in all the regions stu died with IC(50)s in the mu M range. 4. It is suggested that the decre ase in the density of the 5-HT1 sites in rat hippocampus might contrib ute to the nootropic action of adafenoxate.