Abstract
Objective: In recent years besides dopaminergic imbalance exhibition of other possible mechanisms like inflammation and serotonergic abnormalities have pointed out the need for new antipsychotic drugs. In this study our aim was investigating the effects of atorvastatin and melatonin in experimental psychosis model in rats.
Materyal and Methods: Apomorphine-induced stereotypy has been used as a convenient method for in vivo screening of dopamine agonists or antagonists, and assessment of dopaminergic activity. All rats were observed and assessed singly in the Plexiglas cage, 7 (n=6) groups of rat were administered atorvastatin (10, 20 mg/kg, i.p.), melatonin (10, 20 mg/kg, i.p.), 1% ethanol sham (1 ml/kg, i.p.) chlorpromazine (1 mg/kg; i.p.) or isotonic NaCl (1 ml/kg, i.p.). After apomorphine administration, the rats were immediately placed back into the metal cages and observed for stereotypic and rearing behaviors for 15 minutes.
Results: Whereas 20 mg/kg of atorvastatin and 20 mg/kg of melatonin decreased rearing behavior scores compared to saline group significantly (p<0.05). 10 mg/kg of atorvastatin and 20 mg/kg of melatonin groups had decreased stereotypy scores (p<0.05), but 20 mg/kg of atorvastatin caused a stronger decrease (p<0.001).
Conclusions: In the clinical practice when antipsychotic’s side effects and non-satisfactory treatment options are regarded, it is obvious that new drugs like atorvastatin and melatonin with different mechanisms (like anti-inflammatory, neuroprotective effects) of actions will enlighten the future studies.

Key words: psychosis, statin, melatonin, stereotypy