5-HT1A-RECEPTOR SUBTYPE MEDIATES THE EFFECT OF FLUVOXAMINE, A SELECTIVE SEROTONIN REUPTAKE INHIBITOR, ON MARBLE-BURYING BEHAVIOR IN MICE

The effect of fluvoxamine, a selective serotonin (5-HT) reuptake inhib itor, was studied in a model of anxiety and/or obsessive compulsive di sorder (OCD) in mice. In the anxiety/OCD model, marble-burying behavio r, marble-burying was significantly suppressed by fluvoxamine at 30 an d 60 mg/kg, p.o. and the monoamine reuptake inhibitor clomipramine, at 60 mg/kg, p.o. No suppressive effect, however, was observed by the se lective norepinephrine reuptake inhibitor desipramine at doses from 15 to 60 mg/kg, p.o. Suppressive effects were obtained by the serotonerg ic anxiolytic buspirone at 30 and 60 mg/kg, p.o. and the benzodiazepin e anxiolytic diazepam at 10 mg/kg, p.o. The effect of fluvoxamine on m arble-burying was slightly attenuated after repeated administration. O n the other hand, both the effects of buspirone and diazepam completel y disappeared after repeated administration. Effect of fluvoxamine on the marble-burying was unaffected by the 5-HT2 antagonist ritanserin. However, the 5-HT1A antagonist NAN-190 (1-(2-methoxyphenyl)-4-[4-(2-ph thalimido)butyl] piperazine) inhibited the suppressive effect of fluvo xamine on the marble-burying. From these results, the 5-HT1A-receptor subtype may be involved in the suppressive effect of fluvoxamine on th e marble-burying, but the 5-HT2-receptor subtype is not involved in th is effect.