Anxiolytic effects of fractions obtained from Passiflora incarnata L. in the elevated plus maze in mice
The anxiolytic effects of passion flower (Passiflora incarnata L.) have been confirmed in several pharmacological studies [1–3], however, the compounds responsible for this effect are still a matter of debate. The purpose of this study was to characterize the putative anxiolytic-like activity of fractions prepared from a hydroethanolic extract using the elevated plus-maze (EPM) in mice. The fractions were prepared as published recently , yielding into a butanol, petroleum ether and chloroform fraction. Male BL6/C57J mice were either treated orally with each fraction in three different concentrations according to their percent amount in the extract or the positive control diazepam (1.5mg/kg). From the tested fractions, the butanol fraction showed significant increases in the number of open arm entries in the EPM in concentrations of 2.1mg/kg and 4.2mg/kg corresponding to 150 and 300mg/kg of the original extract. The highest activity was found for the chloroform fraction in doses of 0.17mg/kg (10.0±1.9, p<0.001) and 0.34mg/kg (6.6±0.86; p<0.05) which corresponds to a total extract dose of 150 and 300mg/kg respectively. Interestingly, the petroleum ether fraction did not show any effects in the elevated plus maze. A sedative effect of each of the fractions could be excluded, since none of the compounds had an influence on the total distance that the animals covered during the observation period. Our results suggest that the active principle of passion flower seems to be in the chloroform fraction and to a lower extend in the butanol fraction.
References: 1. Soulimani, R. et al. (1997)J Ethnopharmacol 57(1): 11–20.
2. Grundmann, O. et al. (2009) Pharmazie 64: 63–64.
3. Grundmann et al. (2008) Planta Medica 74(15): 1769–1773.
4. Holbik, M. (2010) Diploma Thesis, University of Vienna.