title: Hydrogen sulfide decreases reactive oxygen in a model of lung transplantation.
abstract: BACKGROUND
  Ischemia-reperfusion injury is a common complication after lung transplantation. Ischemia-reperfusion injury is thought to be mediated by reactive oxygen species (ROS). Hydrogen sulfide (H(2)S) is a novel agent that has been previously shown to scavenge ROS and slow metabolism. We evaluated the effect of infused H(2)S on the presence of ROS after reperfusion in an ex vivo model of lung transplantation.
  
  
  METHODS
  Heart-Lung blocks were recovered from New Zealand white rabbits (n = 12) and cold stored in Perfadex solution for 18 h. After storage, the heart-lung blocks were reperfused ex vivo with donor rabbit blood. In the treatment group (n = 7), a bolus of sodium H(2)S was added at the beginning of reperfusion (100 μg/kg) and continuously infused throughout the 2-h experiment (1 mg/kg/h). The vehicle group (n = 5) received an equivalent volume of saline. Serial airway and pulmonary artery pressures and arterial and venous blood gases were measured.
  
  
  RESULTS
  Oxygenation and pulmonary artery pressures were similar between the 2 groups. However, treatment with H(2)S resulted in a dramatic reduction in the presence of ROS after 2 h of reperfusion (4,851 ± 2,139 versus 235 ± 462 related fluorescence units/mg protein; P = 0.003). A trend was seen toward increased levels of cyclic guanosine monophosphate in the H(2)S-treated group (3.08 ± 1.69 versus 1.73 ± 1.41 fmol/mg tissue; P = .23).
  
  
  CONCLUSIONS
  After prolonged ischemia, infusion of H(2)S during reperfusion was associated with a significant decrease in the presence of ROS, a suspected mediator of ischemia-reperfusion injury. To our knowledge, the present study represents the first reported therapeutic use of H(2)S in an experimental model of lung transplantation.
authors.affiliation: Division of Cardiac Surgery, Johns Hopkins Medical Institutions, Baltimore, Maryland 21287, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: George
authors.forename: George J
authors.initials: GJ
authors.lastname: Arnaoutakis
authors.forename: Claude A
authors.initials: CA
authors.lastname: Beaty
authors.forename: Simran K
authors.initials: SK
authors.lastname: Jandu
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Santhanam
authors.forename: Dan E
authors.initials: DE
authors.lastname: Berkowitz
authors.forename: Ashish S
authors.initials: AS
authors.lastname: Shah
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D004195:Disease Models, Animal; D006862:Hydrogen Sulfide / Q000494:pharmacology*; D016040:Lung Transplantation; D010477:Perfusion; D011651:Pulmonary Artery / Q000502:physiology; D011669:Pulmonary Wedge Pressure / Q000502:physiology; D011817:Rabbits; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000378:metabolism*; D016896:Treatment Outcome
chemical_list: D017382:Reactive Oxygen Species; D006862:Hydrogen Sulfide