Antinociceptive, antipyretic and anti-inflammatory effects of Clerodendrum phlomidis in mice and rats

Abstract

The ethanolic extract of Clerodendrum phlomidis L. belonging to the family of Verbenaceae was evaluated for its antinociceptive, antipyretic and anti-inflammatory activity in mice and rats respectively. Analgesic activity was studied by using acetic acid-induced mouse withering test, hot water tail immersion method and eddy’s hot plate method in mice. The antipyretic activity was evaluated against yeast induced pyroxia in rat and anti-inflammatory activity was evaluated by carrageenan-induced hind paw edema and its probable mechanism evaluated in rats. The preliminary phytochemical screening and acute toxicity studies were carried out. C. phlomidis extract showed a dose dependent significant reduction of the number of writhes (P<0.001) with 800 mg.kg-1 body weight dose giving the highest reduction. The extract showed an insignificant elongation of the hot plate reaction time (P<0.05) and it produced a significant reduction in hot-water tail immersion method. C. phlomidis extract showed significant reduction in brewer’s yeast induced hyperthermia in rats. In the carragenan induced paw edema, a dose dependent significant inhibition was observed (P<0.001) between the 2nd and 5th hr. Preliminary phytochemical screening of the extracts showed that the carbohydrates,
proteins, amino acids, phytosterols, alkaloids, fats, fixed oils, flavonoids and gums were present in the plant extract. It is clear that the ethanolic extract of C. phlomodis has significant analgesic and anti-inflammatory
activity. Inhibition of the synthesis of prostaglandins and other inflammatory mediators probably account for the analgesic and anti-inflammatory properties.

Key words: C. phlomidis, antinociceptive, antipyretic, anti-inflammatory, arthritis.