Evaluation of local anesthetic and antipyretic activities of Cinchona alkaloids in some animal models
Purpose: To evaluate the local anesthetic and antipyretic activities of an aqueous extract of Cinchona officinalis (C. officinalis) in experimental animal models.
Methods: Various doses of the aqueous extract was tested for its local anesthetic activity in guinea pigs and frogs using intracutaneous and plexus anesthesia, respectively. For comparison, 2 % xylocaine was used as a reference drug. The anti-pyretic activity of the aqueous extract was determined by Brewer’s yeast-induced pyrexia in rats, using aspirin (300 mg/kg) as reference.
Results: C. officinalis extract, at concentrations of 10 and 20 %, produced significant anesthetic effects, of 72.12 and 88.08 %, respectively, compared with 96.86 % anesthetic effect of 2 % standard xylocaine (p < 0.001). In the plexus model, the mean onset of anesthetic effect was recorded at 6.44 ± 0.68 min versus 3.86 ± 0.42 min (p < 0.001) for the standard drug. Single administration of the extract (100, 200 and 400 mg/kg) showed significant dose-dependent anti-pyretic activity throughout the observation period, which was comparable to the standard aspirin group.
Conclusions: The findings suggest that the aqueous extract of C. officinalis has significant local anesthetic and anti-pyretic activities in rats.
Keywords: Cinchona officinalis, Antipyretic, Aspirin, Local anesthesia, Cinchona alkaloids, Xylocaine