title: Advances in the Physiology of GPR55 in the Central Nervous System.
abstract: BACKGROUND
  The G protein-coupled receptor 55 (GPR55) is a mammalian orphan receptor that awaits a formal classification. There are an increasing number of reports directed to know the physiology and pathophysiology of this receptor. Lamentably, its functions in the central nervous system (CNS) have been scarcely elucidated.
  
  
  METHODS
  A bibliographic search in PubMed database about GPR55 actions in the CNS was made. The information was grouped for brain structures to facilitate the interpretation. Finally, we constructed a schematic representation of the current knowledge about the potential participation of GPR55 in some physiological and pathophysiological events.
  
  
  RESULTS
  Seventy nine papers were included in the review. Only few of them showed data about GPR55 (mRNA/protein) expression in multiple brain areas. The rest showed findings in different preparations both in vitro and in vivo conditions that allowed us to speculate a potential activity of GPR55 in the different brain areas.
  
  
  CONCLUSIONS
  GPR55 mRNA is expressed in several brain areas as the hippocampus, hypothalamus, frontal cortex and cerebellum; but due to the lack of information, only some speculative information about its function in these regions has been suggested. Therefore, this review provide relevant information to motivate further research about GPR55 physiology/pathophysiology in the CNS.
authors.affiliation: Department of Physiology, Faculty of Medicine, UNAM, P.O. Box: 70-250, Mexico City. Mexico.
authors.forename: Bruno A
authors.initials: BA
authors.lastname: Marichal-Cancino
authors.affiliation: Department of Physiology, School of Medicine, National Autonomous University of Mexico; Mexico City. Mexico.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Fajardo-Valdez
authors.affiliation: Coordination of Psychobiology, School of Psychology, National Autonomous University of Mexico, Mexico City. Mexico.
authors.forename: Alejandra E
authors.initials: AE
authors.lastname: Ruiz-Contreras
authors.affiliation: Department of Physiology, Faculty of Medicine, UNAM, P.O. Box: 70-250, Mexico City. Mexico.
authors.forename: Monica
authors.initials: M
authors.lastname: Mendez-Díaz
authors.affiliation: Department of Physiology, Faculty of Medicine, UNAM, P.O. Box: 70-250, Mexico City. Mexico.
authors.forename: Oscar
authors.initials: O
authors.lastname: Prospero-García
mesh_terms: D000818:Animals; D002186:Cannabinoids / Q000378:metabolism / Q000494:pharmacology; D002490:Central Nervous System / Q000187:drug effects / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006801:Humans; D011597:Psychomotor Performance / Q000502:physiology; D039781:PubMed / Q000706:statistics & numerical data; D043882:Receptors, Cannabinoid; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism / Q000502:physiology*; D012677:Sensation / Q000502:physiology
chemical_list: D002186:Cannabinoids; C524885:GPR55 protein, human; D043882:Receptors, Cannabinoid; D043562:Receptors, G-Protein-Coupled
keywords: GPR55; central nervous system; endocannabinoid system; lysophosphatidylinositol; procedural memory