title: Nitrous oxide promotes hyperhomocysteinemia in levodopa treated rats.
abstract: BACKGROUND
  This study investigated whether brief exposure to nitrous oxide (N(2)O) exacerbates levodopa-induced hyperhomocysteinemia, and if co-treatment with folate or entacapone could reduce total plasma homocysteine (tHcy) levels.
  
  
  METHODS
  MALE WISTAR RATS (N=9 PER GROUP) WERE RANDOMLY TREATED WITH VEHICLE/N(2)O (GROUP 1), levodopa/nitrogen (group 2), levodopa/N(2)O (group 3), levodopa/N(2)O+folate (group 4), or levodopa/N(2)O+entacapone (group 5). tHcy was measured at 12 min, 4, 8, and 12 h after anesthesia.
  
  
  CONCLUSIONS
  The combination of N(2)O-exposure and levodopa treatment significantly increased tHcy in rats. This hyperhomocysteinemia could be prevented by entacapone but not folate co-administration.
authors.affiliation: Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01655, USA. Nils.Henninger@umassmed.edu
authors.forename: Nils
authors.initials: N
authors.lastname: Henninger
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.forename: Jürgen G
authors.initials: JG
authors.lastname: Okun
authors.forename: Stefan
authors.initials: S
authors.lastname: Schwab
authors.forename: Martin
authors.initials: M
authors.lastname: Krause
mesh_terms: D018712:Analgesics, Non-Narcotic / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D002396:Catechols / Q000494:pharmacology; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006710:Homocysteine / Q000097:blood; D020138:Hyperhomocysteinemia / Q000097:blood / Q000139:chemically induced*; D007118:Immunoassay / Q000379:methods; D007980:Levodopa; D008297:Male; D009570:Nitriles / Q000494:pharmacology; D009609:Nitrous Oxide / Q000494:pharmacology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
chemical_list: D018712:Analgesics, Non-Narcotic; D002396:Catechols; D004791:Enzyme Inhibitors; D009570:Nitriles; D006710:Homocysteine; D007980:Levodopa; C071192:entacapone; D009609:Nitrous Oxide