Evaluation of local anesthetic and antipyretic activities of Cinchona alkaloids in some animal models

Yan Li,Jun Tian

doi:10.4314/tjpr.v15i8.10

Abstract

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

Highlights

The use of medicinal plants in treating ailments has been an integral part of traditional medicine for centuries
The aqueous extract, tested at up to 2000 mg/kg, was found to be non-toxic
The local anesthetic activity results of the samples in the guinea pig wheal test are presented in Table 1, which shows that the

Summary

INTRODUCTION

The use of medicinal plants in treating ailments has been an integral part of traditional medicine for centuries. Cinchonidine can comprise up to 16 % by mass of total tree bark Most of these extracts have been utilized in the food and beverage industry as bitter additives. They have been used as an important anti-malarial drug; as a muscle spasm relaxant agent; and as a cardiac depressant (anti-arrhythmic). Because of their increasing commercial importance, several cinchona species are widely cultivated in various parts of the world [2,3]. An acute oral toxicity study was carried out using the aqueous extract (0–2000 mg/kg) and the acute toxicity method prescribed by the Organization of Economic Co-operation and Development (OECD) Guidelines (No 423) [6]

Evaluation of local anesthetic activity

Evaluation of antipyretic activity

RESULTS

DISCUSSION

CONCLUSION

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