Astrocyte-neuron lactate shuttle and pain

Plastic change of spinal neuronal network modifies the sensitivity to touch, pain, and other sensory inputs. Some of pathological aberrant increases the release of inflammatory cytokines or excitatory neurotransmitters and induces plastic changes of spinal dorsal horn (SDH) neurons to enhance the nociceptive transmission. Recent studies revealed that glial cells are morphologically or functionally changed in chronic pain and regulate neuronal functions by various bioactive substances. In particular, astrocyte is considered to supply l -lactate to neurons as energy for maintaining and facilitating neurotransmission. This system, so-called astrocyte-neuron lactate shuttle (ANLS), is observed in various brain regions and is probed to regulate their neuronal plasticity. As SDH astrocytes are generally known to be activated in neuropathic pain model animals, functional changes of ANLS are also to be induced. This chapter goes on to discuss the causal relationship between the ANLS and pathological pain, as well as the mechanisms of SDH nociceptive neurotransmission.