Antipsychotic-like effect of minocycline in a rat model.

Tetracycline antibiotic drug minocycline has strongly neuroprotective and anti-inflammatory effects. Minocycline has also remarkable brain tissue penetration, is clinically entirely tolerated and properly absorbed when taken orally. In our study, we class with the effects of minocycline and chlorpromazine, a conventional antipsychotic drug, by evaluating the novelty-induced rearing, apomorphine-induced stereotypic behavior, and brain MDA levels in rats. Four groups of rat (n = 7) were applied with minocycline (50 and 100 mg/kg, i.p.), chlorpromazine (1 mg/kg, i.p.), or isotonic saline (1 mL/kg, i.p.). One hour later, apomorphine (2 mg/kg, s.c.) was applied to each rat. Our results showed that both doses of minocycline significantly decreased the rearing behavior in rats, whereas the decrease with chlorpromazine was higher. Minocycline also decreased the stereotypy scores in a dose-dependent manner. We concluded that minocycline has beneficial effects on rearing behavior and stereotypy, which are accepted to be indicators of antipsychotic effect. Taken together, minocycline, as an anti-oxidant and cytoprotective agent, can be useful in neuroprotection especially on early stages of psychosis or prepsychotic patients with insignificant symptoms. Minocycline is worthy of being investigated for its anti-psychotic effects as a primary or an adjunctive drug.