Concentration-Effect Relationship of Intrapritoneal Administration of 1, 25 (Oh) 2-Vitamin D in A Chronic Constriction Model of Neuropathic Pain

Introduction: the presence of nuclear receptors of 1,25 dihydroxy vitamin d3 (1,25 vit d3), the biologically active metabolite of vitamin d, in neurons and glial cells indicates the biological effect of this vitamin in the nervous system. the present experiment was conducted to identify the effects of different doses of 1,25 vit d3 on mechanical and cold allodynia in rodent model of neuropatinc pain. methods: a mononeuropathy was produced by chronic constrictive injury (cci) of the sciatic nerve. 1,25 vit d3 (0.3, 0.6,1μg/kg) was administered by an i.p. injection every 2 days during a month after cci. mechanical and cold allodynia were evaluated by von frey filament and acetone respectively. results: these findings revealed the exaggerated responses in the group which received cci. the group which was treated by 1μg/kg of 1,25 vit d3 showed a significant reduction in pain behavior. injection of 1,25 vit d3 did not change the response of animals to the acetone drop and von frey filament. discussion: our results showed that antinoceptive effect of 1,25 vit d3 in a rodent neuropathic pain model is dose dependent and this vitamin may provide new approach for treatment of chronic pain.