Spinal γ-aminobutyric acid interneuron plasticity is involved in the reduced analgesic effects of morphine on neuropathic pain

Morphine administration exerts strong analgesic effects against acute pain, but has diminished efficacy against neuropathic pain.1, 8, 23 Rats with peripheral nerve injury, a neuropathic pain model, are less sensitive to the analgesic effects of morphine than normal animals.20 The analgesic effects of opioids are mainly produced by direct post- and pre-synaptic inhibition of nociceptive transmission in the dorsal horn of the spinal cord and activation of the descending inhibitory pathway, including the periaqueductal gray (PAG) and rostral ventromedial medulla (RVM) systems.
Source: The Journal of Pain - Category: Materials Science Authors: Source Type: research