Effects of Hydro-Alcoholic Extract of Salvia Officinalis L. on the Acquisition and Expression of Morphine-Induced Conditioned Place Preference in Mice:An Experimental Study

The rewarding effects of morphine play an important role in its abuse. This study aimed to determine the effects of the hydro-alcoholic extract of the sage plant on the rewarding effects of morphine in female mice.

This experimental research was conducted on 136 female mice. The mice were randomly divided into 17 groups of eight. A conditioned place preference (CPP) procedure was used to investigate the rewarding effects of drugs. On conditioning days, different groups of mice received morphine (1-15 mg/kg) or plant extract (50-150 mg/kg). The control groups also received saline. In the expression test, four groups of mice, after being conditioned with morphine, received plant extract or saline one hour before the CPP test. In the acquisition experiment, four groups of animals, one hour before administration of morphine on conditioning days, received sage extract or saline. On the next day, the CPP test was performed. Data were analyzed using one-way analysis of variance (ANOVA) and Dunnett’s post-hoc test.

Administration of morphine induced a significant CPP in mice (p<0.001). Additionally, administration of plant extract did not affect the expression of morphine CPP (p>0.05). In contrast, the administration of sage extract inhibited the acquisition of morphine-induced CPP (p<0.001).

Hydro-alcoholic extract of sage inhibits the acquisition but not the expression of CPP caused by morphine. Probably, the extract of this plant can be used to prevent the rewarding effects of morphine.