Evaluation of anti-nociceptive effect of methanolic extract of Sambucus nigra leaves using Formalin test and Tail-Flick test models

The interest in plant sources has increased during the last decades in order to obtain new pharmaceutically active compounds. There are many reports on analgesic and anti-inflammatory effects of some plants in traditional medicine. Considering the fact that there are some ambiguities and many difficulties to control pain in todays medicine, traditional medicine could be considered as a valuable source to find new analgesic and anti-inflammatory agents. In Iranian traditional medicine, Elder berry (Sambucus nigra L.) has been reported to have analgesic and anti-inflammatory effects.

In the present study the anti-nociceptive effect of the above mentioned plant has been studied. For evaluating the anti-nociceptive or analgesic effect of this plant, Formalin test and Tail-Flick test have been employed in order to evaluate the effect of Elder berry extract on chronic and acute pain in male Sprague-dawley rats and male NMRI mice respectively.

In this study the methanolic extract of the leaf with HRT (Herbal to Extract Ratio) of 10% has been used. Anti-nociceptive effect of this extract has been compared with anti-nociceptive effect of a standard non-steroidal anti-inflamatory and analgesic drug (Sodium salicylate) by using one-way ANOVA and Tukey HSD.

Extracts of Elder leaves at 200mg/kg and 400mg/kg doses has significant effect on acute and chronic pain. The induced analgesia by extract of this plant is not mediated by the opioid system since naloxon can not prevent the anti-nociceptive effect. The anti-nociceptive effect of this extract at 200mg/kg dose is estimated to bioequivalent with 300mg/kg of sodium salicylate. It has been suggested that this effect of the extract probably is produced by interaction of active components on prostaglandins.