Potentiating effects of Perovskia abrotanoides Karel. on pentobarbital-induced sleep

OBJECTIVE Sleeplessness is the most common sleep disorder. In this study the hypnotic effect of the hydro-alcoholic extract (HAE) of Perovskia abrotanoides Karel. and its water fraction (WF), ethyl acetate fraction (EAF) and n-butanol fraction (NBF) were studied in mice. MATERIALS AND METHODS The test compounds were administered intraperitoneally to mice 30 min before the administration of sodium pentobarbital (30 mg/kg.). Moreover, the influence of flumazenil on the hypnotic effect of the extracts was evaluated. Besides, 30 min after administration of HAE, motor coordination (rota-rod test) was assessed. Additionally, LD50 for HAE was determined and the possible neurotoxicity of the extract was tested in neural PC12 cells. RESULTS The HAE and NBF decreased the latency of sleep (p<0.05), and significantly increased the duration of sleep (p<0.05) induced by pentobarbital. These effects of P. abrotanoides were reversed by flumazenil. HAE did not affect the animals' performance on the rota-rod test. The LD50 value for HAE was found to be 4.8 g/kg. HAE and its fractions did not show neurotoxic effects in cultured PC12 cell line. CONCLUSION The results showed that P. abrotanoides significantly potentiated pentobarbital hypnosis without toxic effect. Probably, its effects are related to its non-polar constituents.