Interaction of alcoholic extracts of hops with pentobarbital and diazepam in mice

The interaction of alcoholic extracts of Magnum, Aroma and wild genotype hops with drugs that lower the activity of the central nervous system (CNS) was studied in mice. Hops drying and preparation of extracts were performed according to standard pharmacological procedures for preparing total alcoholic extracts of medicinal plants, i.e. in a ratio of one part dry herbs to two parts of 70% alcohol, with evaporation to dryness so that the extracts no longer contained any alcohol. The mice received four doses intraperitoneally (i.p.) of 0.5% aqueous solutions of the above-mentioned extracts, which were dissolved in warm physiological solution to make up a 0.5% aqueous solution, 24, 16, 4 and 0.5 hours before pentobarbital (40 mg/kg) or diazepam (3 mg/kg) administration. The hypnotic action of pentobarbital and the effect of diazepam on the coordination of movements (rotating rod method) were measured. It was found that hops extracts influenced the action of the investigated drugs, and that the extracts of the Magnum and Aroma genotypes suppressed the hypnotic action of pentobarbital and diazepam. Tert-butanolic extracts also suppressed the action of these two drugs but to a lesser extent, whereas wild hops extracts did not exert any significant effects compared to controls.