Decrease in endogenous opioids in streptozotocin induced diabetes mellitus correlates with heat hypersensitivity

Background: The clinical symptoms of Diabetic Peripheral Neuropathy (DPN) range from hyperalgesia (increased pain sensitivity) to hypoalgesia (decreased pain sensitivity). The underlying mechanism(s) for these diverse symptoms remains unknown. It is known that the endogenous opioid system (EOS) can modulate pain sensitivity, however the relative contribution of the EOS in DPN is unknown. In this study, the changes that occur in EOS during the course of DPN were characterized. Methods: The changes in EOS were studied in vivo using Streptozotocin-induced C57Bl/6 mice. Heat-induced pain sensitivity was measured by…