Transportation or Noise Is Associated with Tolerance to Myocardial Ischemia and Reperfusion Injury
Autor: | James M. Brown, Prakash Upadhya, Alden H. Harken, Joseph C. Cleveland, Robert T. Rowland |
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Rok vydání: | 2000 |
Předmět: |
Male
medicine.medical_specialty Time Factors Antioxidant medicine.medical_treatment Myocardial Ischemia Diastole Ischemia Myocardial Reperfusion Injury Transportation Endogeny Ventricular Function Left Rats Sprague-Dawley Pathogenesis Reference Values Internal medicine Pressure medicine Animals biology business.industry Myocardium Catalase medicine.disease Adaptation Physiological Enzyme assay Rats Endocrinology Anesthesia Quarantine biology.protein Surgery Noise business Reperfusion injury |
Zdroj: | Journal of Surgical Research. 89:7-12 |
ISSN: | 0022-4804 |
Popis: | Myocardial stress can result in myocellular phenotypic changes including enhanced activity of antioxidant enzyme systems. Accordingly, endogenous tissue antioxidant enzyme activity has been associated with resistance to cardiac ischemia and reperfusion injury. The present study was designed to determine if environmental perturbations could alter myocardial antioxidant enzyme (catalase) activity and function after ischemia. Isolated perfused rat hearts (Langendorff apparatus, 37 degrees C) were subjected to 20 min global ischemia (37 degrees C) and 40 min reperfusion. Rats studied immediately following shipment had increased myocardial catalase activity (1330 +/- 3.5 U/g, P0.05 vs quarantined control) and increased resistance to ischemia and reperfusion injury (end reperfusion developed pressure, DP 55 +/- 4.0 mm Hg, P0.05 vs quarantined control). However, control rats that were quarantined for 4 weeks exhibited a progressive decrease in catalase activity (760 +/- 10 U/g) for 3 weeks of quarantine. There was a concurrent decrease in resistance to myocardial ischemia and reperfusion injury (DP 40 +/- 3.6 mm Hg). Similarly, quarantined rats subjected to construction-related noise levels in excess of 90 dB (A scale) had increased myocardial catalase activity (1140 +/- 3.3 U/g, P0.05) and functional tolerance to ischemia and reperfusion (DP 66 +/- 3.3 mm Hg, P0.05). Finally, rats experiencing 90-dB noise levels for 2 days exhibited increased myocardial catalase activity (1125 +/- 30 U/g, P0.05) and myocardial ischemia and reperfusion injury tolerance (DP 62 +/- 1.7 mm Hg, P0.05). We conclude that variations in environmental conditions can relate to changes in antioxidant defense mechanisms and tolerance to myocardial ischemia and reperfusion injury in the rat. |
Databáze: | OpenAIRE |
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