Evaluation of analgesic and anxiolytic activities of extract from the rhizome of Nelumbo nucifera Gaertn. Nelumbonaceae

Abstract

     In Viet Nam, Nelumbo nucifera Gaertn. Nelumbonaceae is a popular aquatic plant. All parts of Nelumbo nucifera Gaertn. have been used in traditional medicine.  The objective of this study was to evaluate acute toxicity, analgesic and anxiolytic effects of extract of Nelumbo nucifera Gaertn. The percolation method with 70 % ethanol was conducted to obtain the extract. Acute toxicity test was performed on Swiss albino mice at the maximum possible oral dose.  Mice were observed up to 14 days post-treatment. Central analgesic effect was evaluated with tail immersion model, peripheral analgesic effect was evaluated with writhing test using 1 %  acetic acid in mice. The anxiolytic effect was investigated based on Rotarod performance. The results revealed that the maximum possible infralethal dose of the extract at 61,6 g/kg mouse body weight.  The rhizome of Nelumbo nucifera Gaertn. extract at doses of 1,5 g/kg and 3 g/kg mouse body weight show anxiolytic and peripheral analgesic effects but no central analgesic effects. The results of this study would be useful for further study on natural medicine used in supporting the treatment of conditions as stress, insomnia.