Zinc alleviates thermal hyperalgesia due to partial nerve injury

ZINC has recently been shown to alleviate inflammatory hyperalgesia. In the present study, we showed that intrathecal, intraplantar or systemic inject ion of zinc chloride significantly relieved thermal hyperalgesia in rats wi th sciatic nerve injury. Alleviation of thermal hyperalgesia was dose depen dent in each case, although higher doses were required for i.p. injections (ED50 = 13.6 nmole) than for intrathecal (ED50 = 0.05 nmole) or intraplanta r injections (ED50 = 0.3 nmole). Neither intrathecal nor intraplantar zinc chloride influenced thermal nociception in normal rats without nerve injury . The results provide the first evidence that zinc alleviates neuropathic h yperalgesia. NeuroReport 10:1619-1623 (C) 1999 Lippincott Williams & Wilkin s.