PREDICTIVE-VALIDITY OF THE POTENTIATED STARTLE RESPONSE AS A BEHAVIORAL-MODEL FOR ANXIOLYTIC DRUGS

The fear-potentiated startle (PSR) paradigm is a putative behavioral m odel for the determination of anxiolytic properties of drugs. The pres ent study further investigated the predictive validity of the model. P redictive validity is high, when only drugs clinically used as anxioly tics attenuate PSR dose dependently. Results showed that startle poten tiation decreased dose dependently after the administration of the anx iolytics CDP (2.5-10 mg/kg, IP) and alprazolam (1-3 mg/kg, IF). After administration of the clinically non-anxiolytic drugs amitriptyline (2 .5-10 mg/kg, IF), carbamazepine (5-20 mg/kg, IP), fentanyl (0.0025-0.0 4 mg/kg, SC), naloxone (2.5-10 mg/kg, IP), nicotine (0.4-1.6 mg/kg, IP ), alcohol (500-2000 mg/kg, IP), and d-amphetamine (0.6-2.4 mg/kg, IP) , a dose-dependent decrease in startle potentiation was not found. The PSR correctly discriminated most of the drugs tested in clinically an xiolytic and clinically non-anxiolytic drugs. However, haloperidol beh aved as a false positive, and results of nicotine and alcohol were at variance with results reported by others.