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Nayak DU, Karmen C, Frishman WH, Vakili BA. Antioxidant vitamins and enzymatic and synthetic oxygen-derived free radical scavengers in the prevention and treatment of cardiovascular disease. HEART DISEASE (HAGERSTOWN, MD.) 2001; 3:28-45. [PMID: 11975768 DOI: 10.1097/00132580-200101000-00006] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Oxygen-derived free radical formation can lead to cellular injury and death. Under normal situations, the human body has a free radical scavenger system (catalase, superoxide dismutase) that can detoxify free radicals. Antioxidant vitamins and enzymatic and synthetic oxygen-derived free radical scavengers have been used clinically to prevent the formation of oxidized LDL and to prevent reperfusion injury, which is often caused by free radicals. In this article, the pathogenesis of free radical production and cell injury are discussed, and therapeutic approaches for disease prevention are presented.
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Affiliation(s)
- D U Nayak
- Department of Medicine, New York Medical College/Westchester Medical Center, Valhalla, New York, USA
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Frishman WH. William Howard Frishman, MD: a conversation with the editor. Interview by William Clifford Roberts. Am J Cardiol 1998; 81:1323-38. [PMID: 9631971 DOI: 10.1016/s0002-9149(98)00224-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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3
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Qayumi AK, English JC, Godin DV, Ansley DM, Loucks EB, Lee JU, Kim CW. The role of platelet-activating factor in regional myocardial ischemia-reperfusion injury. Ann Thorac Surg 1998; 65:1690-7. [PMID: 9647083 DOI: 10.1016/s0003-4975(98)00275-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND This swine model was designed to elucidate the role of platelet-activating factor in regional myocardial ischemia-reperfusion injury. METHODS In groups 1 and 2 (n = 12 each), the left anterior descending coronary artery was ligated for 60 minutes to induce regional myocardial ischemia followed by 6 hours of reperfusion. Group 1 received the platelet-activating factor antagonist TCV-309 before ischemia, whereas group 2 did not. Group 3 (n = 3) had a sham operation. RESULTS Animals in group 2 exhibited significant (p < 0.05) hemodynamic instability and myocardial depression during the reperfusion period. Despite preventive measures, 7 of the 12 animals experienced severe dysrhythmias in the form of atrial and ventricular fibrillation leading to cardiac arrest. In contrast, animals in group 1 in whom the effects of platelet-activating factor were blocked by the specific platelet-activating factor receptor antagonist TCV-309 were hemodynamically stable and had significantly (p < 0.05) better myocardial function. This significant difference in global myocardial function between the groups was observed in the presence of similar morphologic findings and regional myocardial function. CONCLUSIONS These results suggest that platelet-activating factor has a definite influence on global myocardial dysfunction associated with regional myocardial ischemia-reperfusion injury.
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Affiliation(s)
- A K Qayumi
- Department of Surgery, The University of British Columbia, Vancouver Hospital and Health Sciences Centre, Canada.
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Stoffel M, Berger S, Staub F, Eriskat J, Jacob K, Baethmann A. The effect of dietary alpha-tocopherol on the experimental vasogenic brain edema. J Neurotrauma 1997; 14:339-48. [PMID: 9199399 DOI: 10.1089/neu.1997.14.339] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
It has become increasingly obvious that free radicals and lipid peroxidation contribute to brain damage from trauma by mediating edema formation and ischemia. It should, therefore, be expected that the actual level of endogenous antioxidants, as for example, vitamin C and E in plasma, has an influence on the extent of free radical-induced injury. In this communication we investigate the effect of dietary changes in the free radical scavenger alpha-tocopherol on posttraumatic cerebral swelling in Sprague-Dawley rats. Low, normal, and high plasma levels of alpha-tocopherol were established by respective diets supplied over 2 weeks. Animals of all groups received the same food without alpha-tocopherol. One group was fed a vitamin E-free diet. The pellet-food for the other animals was supplemented either with 5-mg alpha-tocopherol/100 g or 250-mg alpha-tocopherol/100 g dry mass, respectively. The vitamin E-free diet lowered the alpha-tocopherol level in plasma to 30% of control, whereas supplementation with 250 mg/100 g led to a plasma concentration of 200% of control. The animals were then subjected to a focal cold injury of the left cerebral hemisphere. Twenty-four hours after trauma the brain was removed and the water content of each hemisphere was determined by the wet-dry weight method. Swelling of the traumatized hemisphere was calculated as the difference in weight between the traumatized and contralateral control hemisphere. The 2-week alpha-tocopherol supplementation or -deletion diet, respectively, did not either afford significant reduction or lead to an enhancement of traumatic brain swelling. Likewise, the increase in brain water content of the traumatized hemisphere was not affected. It is concluded that supplementation or depletion of alpha-tocopherol for 2 weeks, resulting in a marked increase or decrease of the vitamin E plasma level, does not influence formation of posttraumatic vasogenic brain edema.
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Affiliation(s)
- M Stoffel
- Klinikum Grosshadern, Ludwig-Maximilians-University, München, Germany
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Barut S, Canbolat A, Bilge T, Aydin Y, Cokneşeli B, Kaya U. Lipid peroxidation in experimental spinal cord injury: time-level relationship. Neurosurg Rev 1993; 16:53-9. [PMID: 8483520 DOI: 10.1007/bf00308614] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Damage which occurs following spinal traumas is often irreversible. During recent years free oxygen radicals formed due to the pathological changes following neural tissue ischemia have been identified as being responsible for the ethio-pathogenesis of such damage. In our experimental study, model lesions are formed in spinal cords of rats by standard trauma. Malondialdehyde (MDA), a lipid peroxidation product, was measured in the spinal tissues distal to the trauma in order to examine indirectly the time-quantity relationship of free oxygen radicals in the area. For this study 60 rats in six groups, including one control group, were used to determine the formation of MDA. Under a surgical microscope, the spines of all rats were exposed by C5-Th6 laminectomy, and pressure was applied to the spinal cords of animals, except the members of the control group, at the level of C7 by a Yaşargil aneurysm clip. MDA was measured in spinal cord tissues in order to determine free oxygen radicals at the first and fifteenth minutes and at the first, second, and fourth hours. The statistical evaluation of the findings revealed a significant increase in MDA, starting from the 15th minute after the compression, reaching a maximum at 1 hour, and then decreasing. This observation may provide an important guide for studies on prevention of neural destruction.
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Affiliation(s)
- S Barut
- Department of Neurosurgery, Taksim Hospital, Istanbul, Turkey
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Siminiak T, Ozawa T. Neutrophil mediated myocardial injury. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1993; 25:147-56. [PMID: 8444312 DOI: 10.1016/0020-711x(93)90002-v] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
1. Activated polymorphonuclear neutrophils (PMN) were shown to exacerbate ischemic myocardial injury and their activation is modulated by complement system, platelet activating factor, arachidonic acid metabolites, adenosine and nitric oxide. 2. Mechanisms of injurious PMN effect on ischemic myocardium are related to both mechanical and biochemical processes. 3. Activated PMN aggregate and adhere to endothelium that results in capillary plugging and subsequent impairment of coronary blood flow as well as participating in the development of endothelial cell edema. 4. PMN-related biochemical damage of ischemic myocardium is a result of the release of cytotoxic free oxygen radicals and proteolytic enzymes as well as vasoconstrictor leukotriene B4 and leukotoxin.
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Affiliation(s)
- T Siminiak
- Academy of Medicine, Department of Intensive Therapy, Poznan, Poland
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8
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Stewart S. Current theories and therapies relating to acute myocardial infarction and reperfusion injury. Intensive Crit Care Nurs 1992; 8:104-12. [PMID: 1611284 DOI: 10.1016/0964-3397(92)90039-m] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Acute myocardial infarction (AMI) was previously treated with conservative strategies that allowed the process of ischaemia to proceed uninterrupted. The resultant myocardial necrosis and reduced ventricular function were accepted outcomes. The emergence of thrombolytic agents such as streptokinase and tissue plasminogen activator (tPA) revolutionised the management of coronary artery occlusion, yet the spectre of further myocardial necrosis and ventricular dysfunction remains. The concept of 'reperfusion injury', an acute process described as occurring after thrombolysis of a coronary artery occlusion and referring to an unexpected loss of ventricular function, has been extensively researched. Current research papers describing the mechanisms involved appear either to emphasise those processes that occur within the actual myocytes, or those events within the coronary vasculature. In most papers however, oxygen free radicals (OFRs) are accepted as mediators of cellular injury; despite the debate surrounding their primary source. Efforts to minimise the effects of primary ischaemia and subsequent 'reperfusion injury', appear to be focused upon restoring cardioprotection against the increased levels of these damaging molecules. Scavenging agents such as N-acetylcysteine (NAC) which can also assist in dilating coronary vessels as well as preventing further platelet aggregation, when combined with glyceryl trinitrate (GTN), are being closely scrutinised. Despite the advances made, the processes within the myocardium remain somewhat a mystery and the search continues for more effective strategies to ensure myocardial viability and long-term function. Critical care nurses need not only to be aware of the aim of these new strategies, but should also be conscious of their effect on the patients receiving them.
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van Gilst WH, Kingma JH. Early intervention with angiotensin-converting enzyme inhibitors during thrombolytic therapy in acute myocardial infarction: rationale and design of captopril and thrombolysis study. CATS investigators group. Am J Cardiol 1991; 68:111D-115D. [PMID: 1746415 DOI: 10.1016/0002-9149(91)90267-o] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The adjunctive use of angiotensin-converting enzyme (ACE) inhibitors with thrombolytic therapy early during acute myocardial infarction offers theoretic advantages. In the acute phase, captopril may scavenge free radicals, blunt the catecholamine response, elicit coronary vasodilation, and increase prostacyclin and bradykinin levels. In the chronic phase, ventricular remodeling may be attenuated. At present, a large number of controlled clinical trials mainly focusing on the effects of ACE inhibition in the chronic phase are underway. Only a few studies concentrate on the effect of acute intervention with ACE inhibitors in ischemia-reperfusion, i.e., thrombolysis in myocardial infarction. In April 1990 under auspices of the Interuniversity Cardiology Institute of the Netherlands, a large nationwide acute intervention trial with captopril in 280 patients receiving thrombolytic therapy was started, the Captopril and Thrombolysis Study (CATS). The primary hypothesis of CATS supposes a very early effect of ACE inhibition on evolving myocardial damage due to ischemia and the consequences of early reperfusion. This will be evaluated by serial echocardiography, Holter monitoring and neurohumoral measurements immediately on thrombolysis and during the first year after myocardial infarction.
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Affiliation(s)
- W H van Gilst
- Department of Clinical Pharmacology, University of Groningen, The Netherlands
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Sergeev PV, Snegireva GV, Gukasov VM, Gatsura VV. Correlation between antioxidant and anti-ischemic effects of some energy-yielding compounds. Bull Exp Biol Med 1991. [DOI: 10.1007/bf00841363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Siminiak T, Wysocki H, Veit A, Maurer HR. The effect of selected antiarrhythmic drugs on neutrophil free oxygen radicals production measured by chemiluminescence. Basic Res Cardiol 1991; 86:355-62. [PMID: 1958173 DOI: 10.1007/bf02191532] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The evidence that free oxygen radicals produced by polymorphonuclear neutrophils (PMN) participate in generation of reperfusion arrhythmias is well documented. The in vitro effect of selected antiarrhythmic drugs on PMN free radicals production was evaluated by luminol- (LuCL) and lucigenin- (LgCL) amplified chemiluminescence stimulated with opsonized zymosan (o.z.) and phorbol myristate acetate (PMA). Fast sodium channel inhibitors varied in the influence on PMN chemiluminescence: from an inhibition in all models studied by procainamide, to lack of an effect by mexiletine. Propafenone, similarly to ajmaline and verapamil, inhibited LuCL stimulated with PMA, as well as LgCL after stimulation with both PMA and o.z. Bretylium tosylate decreased LuCL stimulated with both inducers, with no effect on LgCL. Amiodarone in high concentrations inhibited both LuCL and LgCL. beta-blockers propranolol and practolol impaired LuCL stimulated with o.z., as well as LgCL induced with PMA, whereas alpha-blocker phentolamine inhibited LuCL and LgCL stimulated with both inducers. The drugs' effect on PMN free oxygen radicals production may constitute an additional mechanism of their activity.
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Affiliation(s)
- T Siminiak
- Academy of Medicine, Department of Intensive Therapy, Poznań, Poland
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12
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Becker RC, Harrington R. Recombinant tissue-type plasminogen activator: current concepts and guidelines for clinical use in acute myocardial infarction. Part II. Am Heart J 1991; 121:627-40. [PMID: 1899318 DOI: 10.1016/0002-8703(91)90746-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The extraordinarily high prevalence of coronary heart disease, coupled with the alarming incidence of MI in Western society, has encouraged the investigation and development of pharmacologic agents that can be employed widely, quickly, effectively, and safely. Recombinant t-PA has played a vital role in the treatment of MI, restoring coronary arterial patency, limiting infarct size, preserving ventricular function, and improving patient survival. It has been shown to be safe when given to carefully selected patients and, although indications for clinical use have been relatively restricted, they appear to be expanding considerably. Future investigations must continue to focus on patient selection to allow treatment for all patients who would derive benefit and to establish dosing regimens and adjuvant therapies that will maximize coronary reperfusion while concomitantly limiting reocclusion and hemorrhagic complications.
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Affiliation(s)
- R C Becker
- Division of Cardiovascular Medicine, University of Massachusetts Medical School, Worcester 01655
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Hellstrom HR. Myocardial reperfusion injury: an assessment by the spasm of resistance vessel concept of ischemic heart disease. Med Hypotheses 1990; 33:117-24. [PMID: 2259293 DOI: 10.1016/0306-9877(90)90189-l] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Myocardial reperfusion injury will be discussed in context to the spasm of resistance vessel concept of ischemic heart disease. This hypothesis attributes symptoms in this disorder directly to primary spasm of resistance vessels, and is based in part on a study of no-reflow which provided evidence that no-reflow is due to ischemia-induced injury-spasm of resistance vessels. Studies of no-reflow and reperfusion injury are rather similar, and the concept asserts that ischemia-induced injury-spasm causing no-reflow is involved in reperfusion injury. It is recognized that oxygen free radicals cause both myocardial and vascular injury during reperfusion injury, and the concept suggests that vascular injury contributes significantly to reperfusion injury by inducing the sequence of injury-spasm, no-reflow, fresh ischemia, and fresh ischemic reperfusion injury. In keeping with this, the possible involvement of spasm and no-reflow in reperfusion injury occasionally is mentioned. However, it seems to be generally accepted that reperfusion injury is due essentially solely to direct myocardial injury by free radicals, and possible reasons will be explored for a relative disinterest in spasm and no-reflow in reperfusion injury.
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Affiliation(s)
- H R Hellstrom
- Laboratory Service, Veteran Administration Medical Center, Syracuse, New York 13210
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Ko KM, Godin DV. Inhibition of transition metal ion-catalysed ascorbate oxidation and lipid peroxidation by allopurinol and oxypurinol. Biochem Pharmacol 1990; 40:803-9. [PMID: 2117456 DOI: 10.1016/0006-2952(90)90319-g] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Allopurinol and its metabolite oxypurinol inhibited basal oxidation of ascorbate and exerted comparable concentration-dependent inhibitory effects on the oxidation of ascorbate catalysed by cupric ion, but the stimulation produced by ferric ion was affected minimally. UV spectral analysis suggested the formation of an allopurinol-ascorbate-copper ion complex. The oxidation of erythrocyte membrane lipids by ferric ion and cupric ion-t-butylhydroperoxide was also inhibited by allopurinol and oxypurinol, by the metal chelators EDTA and uric acid, and by the antioxidant butylated hydroxytoluene. The metal chelating actions of allopurinol and oxypurinol may be relevant to their protective actions against ischemia/reperfusion injury.
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Affiliation(s)
- K M Ko
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, Canada
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Sochman J, Kolc J, Vrána M, Fabián J. Cardioprotective effects of N-acetylcysteine: the reduction in the extent of infarction and occurrence of reperfusion arrhythmias in the dog. Int J Cardiol 1990; 28:191-6. [PMID: 2394523 DOI: 10.1016/0167-5273(90)90060-i] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We have studied the cardioprotective effect of N-acetylcysteine in the dog. In mongrel dogs of either sex, the left anterior descending coronary artery was ligated for a period of 2 hours behind the origin of its first diagonal branch. After this period, dogs in a treated group were administered 100 mg of N-acetylcysteine/kg body weight while a control group remained untreated. This was followed by a 2-hour period of reperfusion. The extent of necrosis was determined using the triphenyltetrazolium method. Presence or absence of collaterals was established at the same time. The incidence of ventricular arrhythmias was monitored throughout the study. Compared with 11 dogs of the control group, 10 dogs treated with N-acetylcysteine showed a decrease of 32.7% in the extent of infarction. The extent of infarction, expressed as the percentage of the left ventricular myocardium at risk, was 55.0 +/- 7.0% in the control group and 37.0 +/- 12.6% in the treated group (P less than 0.01). N-acetylcysteine also statistically significantly decreased the incidence of ventricular arrhythmias over the period of reperfusion. Compared with the control group, the difference was evident as early as the first 5-10 minutes of reperfusion, becoming most pronounced at the 60th minute (P less than 0.001). We conclude that N-acetylcysteine is effective in limiting the extent of infarction and significantly reduces the incidence of reperfusion ventricular arrhythmias.
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Affiliation(s)
- J Sochman
- Institute for Clinical and Experimental Medicine, Prague, Czechoslovakia
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Reitan JA, Kien ND, Thorup S, Corkill G. Hyperbaric oxygen increases survival following carotid ligation in gerbils. Stroke 1990; 21:119-23. [PMID: 2300978 DOI: 10.1161/01.str.21.1.119] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We studied the effects of graded exposure to hyperbaric (1,875 mm Hg) oxygen therapy in an acute stroke model prepared by unilateral carotid artery interruption in gerbils. Pentobarbital alone, superoxide dismutase alone, two periods of hyperbaric oxygen alone, and each agent combined with hyperbaric oxygen were administered to investigate possible mechanisms of protection from cerebral ischemia. Survival rates and neurologic deficit scores over 5 days in all treated groups were compared with those in a control group. Survival rates in the groups subjected to 2 (63.9 +/- 4.0%) and 4 hours (70.1 +/- 5.2%) of hyperbaric oxygen alone were significantly higher than in the control group (53.6 +/- 4.2%). The group treated with pentobarbital alone also demonstrated increased survival (69.8 +/- 7.0%), but the combination of therapeutic regimens offered no apparent additive protection. By 5 days there were no differences in the neurologic deficit scores of the survivors in the groups. The toxic pulmonary effects of hyperbaric oxygen were assessed in a pilot LD50 study. The pressure used caused no mortality during 4 hours of exposure, and the calculated LD50 was 7.26 hours. This investigation demonstrates that graded doses of hyperbaric oxygen given after the insult increase survival in a gerbil model of stroke.
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Affiliation(s)
- J A Reitan
- Department of Anesthesiology, University of California School of Medicine, Davis 95616
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Chan PS, Cervoni P. Current concepts and animal models of sudden cardiac death for drug development. Drug Dev Res 1990. [DOI: 10.1002/ddr.430190209] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Goldhaber JI, Ji S, Lamp ST, Weiss JN. Effects of exogenous free radicals on electromechanical function and metabolism in isolated rabbit and guinea pig ventricle. Implications for ischemia and reperfusion injury. J Clin Invest 1989; 83:1800-9. [PMID: 2723059 PMCID: PMC303899 DOI: 10.1172/jci114085] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Oxygen-derived free radicals have been implicated in the pathogenesis of cardiac dysfunction during ischemia, postischemic myocardial "stunning," and reperfusion injury. We investigated the effects of oxygen-derived free radicals on cardiac function in intact isolated rabbit hearts and single guinea pig ventricular myocytes. In the intact rabbit ventricle, exposure to free radical-generating systems caused increased cellular K+ efflux, shortening of the action potential duration, changes in tension, and depletion of high energy phosphates similar to ischemia and metabolic inhibition. In patch-clamped single ventricular myocytes, free radical-generating systems activated ATP-sensitive K+ channels, decreased the calcium current, and caused cell shortening by irreversibly inhibiting glycolytic and oxidative metabolism. The results suggest that free radicals generated during ischemia and reperfusion may contribute to electrophysiologic abnormalities and contractile dysfunction by inhibiting glycolysis and oxidative phosphorylation. Inhibition of metabolism by free radicals may be an important factor limiting functional recovery from an ischemic insult after reestablishment of effective blood flow.
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Affiliation(s)
- J I Goldhaber
- Department of Medicine, UCLA School of Medicine, Los Angeles, CA 90024
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Affiliation(s)
- J P Kehrer
- Division of Pharmacology and Toxicology, College of Pharmacy, University of Texas, Austin 78712-1074
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