Antinociceptive effects of curcumin in a rat model of postoperative pain.

Curcumin is a principal ingredient of traditional Chinese medicine, Curcuma Longa, which possesses a variety of pharmacological activities including pain relief. Preclinical studies have demonstrated that curcumin has antinociceptive effects for inflammatory and neuropathic pain. This study examined the effects of curcumin in a rat model of postoperative pain. A surgical incision on the right hind paw induced a sustained mechanical hyperalgesia that lasted for 5 days. Acute curcumin treatment (10-40 mg/kg, p.o) significantly and dose dependently reversed mechanical hyperalgesia. In addition, repeated curcumin treatment significantly facilitated the recovery from surgery. In contrast, repeated treatment with curcumin before surgery did not impact the postoperative pain threshold and recovery rate. All the doses of curcumin did not significantly alter the spontaneous locomotor activity. Combined, these results suggested that curcumin could alleviate postoperative pain and promote recovery from the surgery, although there was no significant preventive value. This study extends previous findings and supports the application of curcumin alone or as an adjunct therapy for the management of peri-operative pain.