title: Multiple mechanisms of microglia: a gatekeeper's contribution to pain states.
abstract: Microglia are gatekeepers in the CNS for a wide range of pathological stimuli and they blow the whistle when things go wrong. Collectively, microglia form a CNS tissue alarm system (Kreutzberg's "sensor of pathology"), and their involvement in physiological pain is in line with this function. However, pathological neuropathic pain is characterized by microglial activation that is unwanted and considered to contribute to or even cause tactile allodynia, hyperalgesia and spontaneous pain. Such abnormal microglial behavior seems likely due to an as yet ill-understood disturbance of microglial functions unrelated to inflammation. The idea that microglia have roles in the CNS that differ from those of peripheral macrophages has gained momentum with the discovery of their separate, pre-hematopoietic lineage during embryonic development and their direct interactions with synapses.
authors.affiliation: Brain Tumor Research Laboratories, The Brain and Mind Research Institute, University of Sydney, Sydney, Australia. manuel@graeber.net
authors.forename: Manuel B
authors.initials: MB
authors.lastname: Graeber
authors.forename: MacDonald J
authors.initials: MJ
authors.lastname: Christie
mesh_terms: D000818:Animals; D063385:Cannabinoid Receptor Modulators / Q000502:physiology; D059350:Chronic Pain / Q000503:physiopathology*; D006801:Humans; D007249:Inflammation / Q000503:physiopathology*; D017628:Microglia / Q000502:physiology*; D009437:Neuralgia / Q000503:physiopathology*
chemical_list: D063385:Cannabinoid Receptor Modulators