In a study produced by Ferrini et al. indicates that morphine-induced hyperalgesia, as neuropathic pain, is a pathological alteration of pain sensitivity whose expression is gated by spinal microglia. Targeting at any level, this microglia-to-neuron cascade is a valuable strategy to improve the use of morphine in chronic pain.
Ferrini F, Trang T, Mattioli TA, Laffray S, Del’Guidice T, Lorenzo LE, Castonguay A, Doyon N, Zhang W, Godin AG, Mohr D, Beggs S, Vandal K, Beaulieu JM, Cahill CM, Salter MW, De Koninck Y. (2013) Morphine hyperalgesia gated through microglia-mediated disruption of neuronal Cl- homeostasis. Nat Neurosci 16:183-92.