title: Alterations of endocannabinoids in cerebrospinal fluid of dogs with epileptic seizure disorder.
abstract: BACKGROUND
  Epilepsy is one of the most common chronic neurological disorders in dogs characterized by recurrent seizures. The endocannabinoid (EC) system plays a central role in suppressing pathologic neuronal excitability and in controlling the spread of activity in an epileptic network. Endocannabinoids are released on demand and their dysregulation has been described in several pathological conditions. Recurrent seizures may lead to an adverse reorganization of the EC system and impairment of its protective effect. In the current study, we tested the hypothesis that cerebrospinal fluid (CSF) concentrations of the endocannabinoids anandamide (AEA) and 2-arachidonoyl glycerol (2AG) are altered in epileptic dogs. Concentrations of AEA and total AG (sum of 2AG and 1AG) were measured in 40 dogs with idiopathic epilepsy and in 16 unaffected, healthy control dogs using liquid chromatography combined with tandem mass spectrometry.
  
  
  RESULTS
  AEA and total AG were measured at 4.94 (3.18 - 9.17) pM and 1.43 (0.90 - 1.92) nM in epileptic dogs and at 3.19 (2.04 - 4.28) pM and 1.76 (1.08 - 2.69) nM in the control group, respectively (median, 25 - 75% percentiles in brackets). The AEA difference between epileptic and healthy dogs was statistically significant (p < 0.05). Values correlated with seizure severity and duration of seizure activity. Dogs with cluster seizures and/or status epilepticus and with seizure activity for more than six months displayed the highest EC concentrations.
  
  
  CONCLUSIONS
  In conclusion, we present the first endocannabinoid measurements in canine CSF and confirm the hypothesis that the EC system is altered in canine idiopathic epilepsy.
authors.affiliation: Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany. Felix.Gesell@tiho-hannover.de.
authors.forename: Felix K
authors.initials: FK
authors.lastname: Gesell
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Zoerner
authors.forename: Christina
authors.initials: C
authors.lastname: Brauer
authors.forename: Stefan
authors.initials: S
authors.lastname: Engeli
authors.forename: Dimitros
authors.initials: D
authors.lastname: Tsikas
authors.forename: Andrea
authors.initials: A
authors.lastname: Tipold
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000134:cerebrospinal fluid; D016022:Case-Control Studies; D004283:Dog Diseases / Q000134:cerebrospinal fluid*; D004285:Dogs; D063388:Endocannabinoids / Q000134:cerebrospinal fluid*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000662:veterinary; D005989:Glycerides / Q000134:cerebrospinal fluid; D008297:Male; D053284:Polyunsaturated Alkamides / Q000134:cerebrospinal fluid; D012008:Recurrence; D012640:Seizures / Q000134:cerebrospinal fluid / Q000662:veterinary*
chemical_list: D001095:Arachidonic Acids; D063388:Endocannabinoids; D005989:Glycerides; D053284:Polyunsaturated Alkamides; C094503:glyceryl 2-arachidonate; C078814:anandamide