title: Anesthetic preconditioning: triggering role of reactive oxygen and nitrogen species in isolated hearts.
abstract: We postulated that anesthetic preconditioning (APC) is triggered by reactive oxygen/nitrogen species (ROS/RNS). We used the isolated guinea pig heart perfused with L-tyrosine, which reacts with ROS and RNS to form strong oxidants, principally peroxynitrite (ONOO(-)), and then forms fluorescent dityrosine. ROS scavengers superoxide dismutase, catalase, and glutathione (SCG) and NO. synthesis inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) were given 5 min before and after sevoflurane preconditioning stimuli. Drugs were washed out before 30 min of ischemia and 120 min of reperfusion. Groups were control (nontreated ischemia control), APC (two, 2-min periods of perfusion with 0.32 +/- 0.02 mM of sevoflurane; separated by a 6-min period of perfusion without sevoflurane), SCG, APC + SCG, L-NAME, and APC + L-NAME. Effluent dityrosine at 1 min reperfusion was 56 +/- 6 (SE), 15 +/- 5, 40 +/- 5(++), 39 +/- 4(++), 35 +/- 4(++) , and 33 +/- 5(++) units ((++)P< 0.05 vs. APC), respectively; left ventricular pressure (%baseline) at 60 min of reperfusion was 30 +/- 5(++), 60 +/- 4, 35 +/- 5(++), 37 +/- 5(++), 44 +/- 4, and 47 +/- 4; and infarct size (%total heart weight) was 50 +/- 5(++), 19 +/- 2, 48 +/- 3(++), 46 +/- 4(++), 42 +/- 4(++), and 45 +/- 2(++). Thus APC is initiated by ROS as shown by improved function, reduced infarct size, and reduced dityrosine on reperfusion; protective and ROS/RNS-reducing effect of APC were attenuated when bracketed by ROS scavengers or NO* inhibition.
authors.affiliation: Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, 53226, USA. novalija@mcw.edu
authors.forename: Enis
authors.initials: E
authors.lastname: Novalija
authors.forename: Srinivasan G
authors.initials: SG
authors.lastname: Varadarajan
authors.forename: Amadou K S
authors.initials: AK
authors.lastname: Camara
authors.forename: Jianzhong
authors.initials: J
authors.lastname: An
authors.forename: Qun
authors.initials: Q
authors.lastname: Chen
authors.forename: Matthias L
authors.initials: ML
authors.lastname: Riess
authors.forename: Neil
authors.initials: N
authors.lastname: Hogg
authors.forename: David F
authors.initials: DF
authors.lastname: Stowe
mesh_terms: D000777:Anesthetics / Q000494:pharmacology*; D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology*; D066298:In Vitro Techniques; D019157:Ischemic Preconditioning, Myocardial / Q000379:methods*; D008738:Methyl Ethers / Q000494:pharmacology; D017202:Myocardial Ischemia / Q000503:physiopathology; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000037:antagonists & inhibitors / Q000378:metabolism; D030421:Peroxynitrous Acid / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015427:Reperfusion Injury / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control; D000077149:Sevoflurane; D013997:Time Factors; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000096:biosynthesis
chemical_list: D000777:Anesthetics; D004791:Enzyme Inhibitors; D008738:Methyl Ethers; D017382:Reactive Oxygen Species; D030421:Peroxynitrous Acid; D009569:Nitric Oxide; D000077149:Sevoflurane; D014443:Tyrosine; C007543:dityrosine; D019331:NG-Nitroarginine Methyl Ester