Inhibitory Effects Of Hs014 On Glutamate Release In Astrocytes Chronically Treated With Morphine

Previous studies have confirmed that the number of glial fibrillary acidic protein positive cells significantly increases during morphine tolerance However morphine tolerance is reversed with melanocortin receptor antagonists and analgesic action is enhanced accordingly However these mechanisms remain unclear In the present study, following addition of morphine to Wistar rat spinal cord astrocytes glutamate levels in the supematant significantly increased (P < 0 05) At 30-120 minutes following addition of intervention agent to spinal cord astrocytes naloxone significantly increased glutamate release in morphine-tolerant model cells (P < 0 05) while melanocortin receptor antagonist HS014 decreased glutamate release (P < 0 05) Additional naloxone and HS014 to astrocytes significantly decreased glutamate release compared with additional naloxone alone (P < 0 01) Results from the present study demonstrated that glutamate release was increased in spinal cord astrocytes co-cultured with morphine Naloxone increased glutamate release, and HS014 reduced glutamate release