Reviews in the neurosciences
January 1, 1999
F Sams-Dodd
Phencyclidine (PCP) produces effects in rats that resemble both positive and negative symptoms of schizophrenia. In the social interaction test, PCP dose-dependently caused stereotyped behavior and social withdrawal. Antipsychotic drugs selectively reduced these PCP-induced behaviors, while non-antipsychotic drugs did not. These findings suggest that PCP effects in the rat social interaction test may serve as a model of schizophrenia symptoms with face and predictive validity, useful for testing new antipsychotic compounds.
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
July 1, 1998
F Sams-Dodd
In rats, continuous administration of D-amphetamine and phencyclidine both induced stereotyped behavior and locomotor hyperactivity, behaviors thought to correspond to positive symptoms of schizophrenia. However, only phencyclidine caused social withdrawal, which models negative symptoms. This finding confirms earlier work showing that amphetamine does not produce social deficits in rats, even when given at high doses over five days.
Neuroscience and biobehavioral reviews
January 1, 1998
F Sams-Dodd
Phencyclidine (PCP) can induce a model psychosis in humans that mimics both positive and negative symptoms of schizophrenia. In the social interaction test, PCP causes stereotyped behavior and social isolation in rats, which can be inhibited by antipsychotic drugs. To further evaluate this model's predictive validity, drugs without antipsychotic activity—diazepam (0.02–17.5 µmol/kg), citalopram (0.62–19.8 µmol/kg), methadone (0.36–5.8 µmol/kg), and naloxone (0.34–22.0 µmol/kg)—were tested. None specifically inhibited PCP-induced behaviors, suggesting that only antipsychotic drugs can do so.
Psychopharmacology
January 1, 1998
F Sams-Dodd
Phencyclidine (PCP) induces behaviors in rats that model aspects of schizophrenia, including hyperactivity, stereotyped behavior, and social isolation. Over a 3-day regimen, dopamine D1-receptor agonists had limited effects on these PCP-induced behaviors, while the D1-antagonist SCH 23391 reduced PCP-induced social isolation, though tolerance developed after 21 days of treatment. The D2/D3/D4-agonist quinpirole worsened and mimicked PCP's social deficits, and the D2/D3-antagonist (-)sulpiride reduced PCP-induced stereotyped behavior and social isolation. A D4-antagonist had no effect. However, similar effects occurred in vehicle-treated rats, suggesting non-specific influences may have been involved.