title: Hydroxyethyl starch macromolecule and superoxide dismutase effects on myocardial reperfusion injury.
abstract: Myocardial reperfusion injury may be due to biophysical changes (e.g., endothelial cell junctional separations), as well as biochemical mechanisms (e.g., oxygen free radical activity). Superoxide dismutase (SOD), a free radical scavenger, may be effective in reducing chemical injury. Fractions of hydroxyethyl starch (HES-Pz), a large macromolecule, have been shown to decrease microvascular permeability associated with reperfusion-induced biophysical alterations. A comparison of SOD to HES-Pz was performed using a canine model of 1-hour left anterior descending coronary artery (LAD) clamping followed by 24 hours of reperfusion. Amounts of the test solution equal to 10% of the dog's blood volume were administered intraatrially to the animals just before release of the LAD clamp. Six dogs received Ringer's lactate, 7 were given 600,000 IU of SOD, 13 received 6% HES-Pz, and 9 were given SOD and HES-Pz. The ratio of infarct to area at risk was 20 +/- 3% in the control dogs receiving Ringer's lactate, 16 +/- 4% in animals receiving SOD alone (p = NS), 6 +/- 3% in dogs receiving HES-Pz alone (p less than 0.05), and 8 +/- 3% in dogs given a combination of SOD and HES-Pz (p less than 0.05). HES-Pz alone and with SOD significantly reduced reperfusion injury, although addition of SOD to HES-Pz did not have an additive effect. Appropriate-sized macromolecules may act by reducing ischemia-induced microvascular permeability.
authors.affiliation: Department of Surgery, College of Physicians and Surgeons, Columbia University, New York, New York.
authors.forename: M C
authors.initials: MC
authors.lastname: Oz
authors.forename: B A
authors.initials: BA
authors.lastname: Zikria
authors.forename: P F
authors.initials: PF
authors.lastname: McLeod
authors.forename: S J
authors.initials: SJ
authors.lastname: Popilkis
mesh_terms: D000818:Animals; D004285:Dogs; D004359:Drug Therapy, Combination; D006895:Hydroxyethyl Starch Derivatives / Q000008:administration & dosage / Q000627:therapeutic use*; D007552:Isotonic Solutions / Q000008:administration & dosage; D009203:Myocardial Infarction / Q000473:pathology / Q000517:prevention & control; D015428:Myocardial Reperfusion Injury / Q000188:drug therapy* / Q000503:physiopathology; D009206:Myocardium / Q000473:pathology; D000077325:Ringer's Lactate; D013482:Superoxide Dismutase / Q000008:administration & dosage / Q000627:therapeutic use*; D013997:Time Factors
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; D000077325:Ringer's Lactate; D013482:Superoxide Dismutase