Is oxidative stress primarily involved in reperfusion injury of the ischemic heart

Journal Article · Mon Dec 31 23:00:00 EST 1990 · Free Radical Biology and Medicine; (United States)

DOI:https://doi.org/10.1016/0891-5849(91)90139-T· OSTI ID:5679315

Nohl, H; Stolze, K; Napetschnig, S; Ishikawa, T ^[1]

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1. Institute of Pharmacology and Toxicology, Vet. Med. Univ., Vienna (Austria)

Reperfusion injury of ischemic organs is suggested to result from metabolic derangements initiating an imbalanced formation of free oxygen radicals. Most investigators in this field have used the spin-trap 5,5'-dimethyl-N-pyrroline-N-oxide (DMPO) to stabilize these short-lived radicals and make them visible by means of the electron spin resonance (ESR) technique. ESR signals obtained from intravascular DMPO were reported to indicate the formation of free OH. radicals and, in some cases, also carbon-centered radicals. We were unable to confirm these findings. Carbon-centered radicals were not obtained irrespectively of conditions studied, while oxygen-centered DMPO-adducts could only be detected in minor amounts. Instead, we observed an ascorbyl-related ESR signal. The addition of ethylenediaminetetraacetic acid (EDTA), which was used by many investigators in this field, was found to greatly influence ESR-spectra of the reperfusion fluid. The ascorbyl radical concentration was clearly reduced and the DMPO-OH. adduct became more prominent. The addition of iron further stimulated this change eliciting a Fenton-type reaction responsible for DMPO-OH.-related ESR spectra in the perfusate after ischemia. Accordingly, we observed the release of iron and ascorbic acid into the perfusate as a consequence of ischemia. We could demonstrate that iron in the presence of ascorbate and EDTA causes both types of radicals detected in the perfusate. DMPO-OH. generation in the presence of EDTA was found to result from free OH. radicals that were not generated in the absence of EDTA.

• OSTI ID: 5679315
• Journal Information: Free Radical Biology and Medicine; (United States), Journal Name: Free Radical Biology and Medicine; (United States) Vol. 11:6; ISSN FRBME; ISSN 0891-5849
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINO ACIDS
ANEMIAS
ANIMALS
ASCORBIC ACID
BIOLOGICAL STRESS
BIOSYNTHESIS
BODY
CARBOXYLIC ACIDS
CARDIOVASCULAR DISEASES
CARDIOVASCULAR SYSTEM
CHELATING AGENTS
DISEASES
EDTA
ELECTRON SPIN RESONANCE
ELEMENTS
HEART
HEMIC DISEASES
HYDROGEN COMPOUNDS
HYDROXIDES
IN VITRO
IRON
ISCHEMIA
MAGNETIC RESONANCE
MAMMALS
METALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
OXYGEN COMPOUNDS
RADICALS
RATS
REAGENTS
RESONANCE
RODENTS
SYMPTOMS
SYNTHESIS
TOXICITY
TRANSITION ELEMENTS
VASCULAR DISEASES
VERTEBRATES
VITAMINS