Albizia zygia (DC.) J.F. Macbr. (Leguminosae-Mimosoideae) root extract exhibits anti-nociceptive and antipyretic activities in murine models.

Ethnopharmacological relevance The root extract of Albizia zygia (DC.) J.F. Macbr. (Leguminosae-Mimosoideae) is traditionally used in the management of pain and fever. However, little scientific data exists in literature to support its use. Aim of study The present study evaluated the anti-nociceptive and antipyretic properties of the hydroethanolic extract of the roots of Albizia zygia in animal models. Materials and methods The analgesic effects were investigated in chemical (acetic acid-induced abdominal writhing and formalin tests), thermal (tail-immersion test) and mechanical (carrageenan-induced hyperalgesia) pain models. Possible mechanisms of anti-nociception were also assessed with antagonists in the formalin test. The anti-pyretic effect was evaluated using the baker yeast-induced pyrexia model in young rats. Results The extract (30–300 mg/kg, p.o .) and positive controls, diclofenac (3–30 mg/kg, i.p.) and morphine (1–10 mg/kg, i.p.), significantly (at least P <0.01) attenuated acetic acid-induced visceral pain, formalin- induced paw pain (both neurogenic and inflammatory), thermal pain as well as carrageenan-induced mechanical hyperalgesia in animals. The anti-nociceptive effect of the extract was reversed (at least P <0.05) by the pre-emptive administration of naloxone and atropine; the administration of theophylline, however, exhibited no significant ( P >0.05) inhibition of anti-nociception. The extract (30–300 mg/kg, p.o ) and paracetamol (15–150 mg/kg, p.o. ) both reversed yeast-induced pyrexia in rats with ED 50 values of 48.59±2.59 and 26.19±1.33 mg/kg respectively. Conclusion The findings indicate that the extract possesses significant anti-nociceptive and antipyretic effects which justify its traditional use in the management of pain and fever. Also, anti-nociceptive effect of the extract involves opioidergic and muscarinic cholinergic mechanisms. [ABSTRACT FROM AUTHOR]