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001-es BibID:BIBFORM041657
Első szerző:Blasig, Ingolf E.
Cím:Inverse relationship between ESR spin trapping of oxyradicals and degree of functional recovery during myocardial reperfusion in isolated working rat heart / Blasig I. E., Ebert B., Hennig C., Pali T., Tosaki A.
Dátum:1990
Megjegyzések:STUDY OBJECTIVE: The aim of the study was to investigate the generation of free oxyradicals as factors in myocardial ischaemia-reperfusion pathology. DESIGN: Isolated perfused rat hearts were subjected to 30 min global ischaemia followed by reperfusion. The spin trap 5,5-dimethyl-1-pyrroline-1-oxide was added to the effluent of the heart to avoid pharmacological interaction with the heart. The effluent was then analysed by electron spin resonance spectroscopy. MATERIALS: Studies were performed on hearts of 51 male Sprague-Dawley rats, weight 300-350 g. MEASUREMENTS AND RESULTS: During reperfusion, the formation of hydroxyl radical adducts of the trap was observed, with a maximal value after 3 min. The initial amount of radicals trapped during the first 3 min of reperfusion showed an inverse correlation with the degree of heart function restored within 30 min of reperfusion. Spearman's rank correlation coefficients were calculated to be -0.734 for heart rate, -0.825 for left ventricular developed pressure, -0.787 for the maximum of its first derivative, -0.787 for coronary flow, and -0.796 for aortic flow (p less than 0.05, n = 10, in each instance). No statistically significant correlation was found between the cumulative amount of radicals trapped in the effluent during the initial phase of reperfusion and the duration of ventricular fibrillation, duration of ventricular tachycardia, or number of ventricular ectopic beats (registered during 30 min reperfusion). CONCLUSIONS: The application of spin trapping to the effluent of isolated perfused hearts allows the generation of oxyradicals to be characterised without interaction of the trap with the heart. It also allows the time course of radical production to be investigated, and can detect relative changes in their intensity. These are important factors in the study of the pathogenic role of free radicals generated during reperfusion of an ischaemic heart.
Tárgyszavak:Orvostudományok Gyógyszerészeti tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Cardioscular Research. - 24 : 4 (1990), p. 263-270. -
További szerzők:Ebert, Berndt Hennig, Christian Pali Tibor Tósaki Árpád (1958-) (kísérletes farmakológus, gyógyszerész)
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
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2.

001-es BibID:BIBFORM041658
Első szerző:Tósaki Árpád (kísérletes farmakológus, gyógyszerész)
Cím:Heart protection and radical trapping by DMPO during reperfusion in isolated working rat hearts / Tosaki A., Blasig I. E., Pali T., Ebert B.
Dátum:1990
Megjegyzések:The purpose of this study was to use a direct method, that of electron spin resonance (ESR) spectroscopy, to demonstrate that reperfusion after a period of ischemia results in a sudden increase in the production of free radicals in the myocardium. Furthermore, the role of free radicals in the development of reperfusion arrhythmias and functional disturbances also was investigated using a 30-min period of global ischemia followed by 30 min of reperfusion in the isolated working rat heart. The spin trapping agent 5,5-dimethyl-1-pyrroline-1-oxide (DMPO) when it perfused the heart, 100 mumoles/liter, during the first 10 min of reperfusion attenuated the development of reperfusion arrhythmias and improved the functional recovery of the heart during reperfusion. Without treatment, 55% of hearts showed irreversible ventricular fibrillation, and this was completely prevented by DMPO. In DMPO-treated hearts, the recovery of heart function was improved; thus, coronary flow, aortic flow, left ventricular developed pressure, and first derivative of left ventricular developed pressure were significantly increased from their maximal control values of 16.2 +/- 1.9 ml/min, 12.7 +/- 0.9 ml/min, 11.1 +/- 0.5 kPa, and 426 +/- 31 kPa/s to 21.8 +/- 1.3 ml/min (p less than 0.05), 28.4 +/- 3.0 ml/min (p less than 0.001), 14.5 +/- 1.0 kPa (p less than 0.01), and 584 +/- 41 kPa/s (p less than 0.01), respectively. Left ventricular end-diastolic pressure was also significantly reduced from its control value of 2.8 +/- 0.2 kPa to 2.1 +/- 0.2 kPa (p less than 0.05), while the recovery of heart rate was not improved by DMPO treatment. Parallel ESR studies using DMPO as spin trap demonstrated the formation of .OH radicals in the effluent of the reperfused hearts. ESR signals of the formed DMPO-OH, alpha N = alpha beta H = 1.48 mT, were observed within the first seconds of reperfusion with peak concentrations after about 3 min. In the first series of ESR studies, DMPO (200 mmol/liter) was mixed up effluent and ESR signals were recorded, while in the second series of studies, DMPO was directly infused into the heart. Both methods were appropriate to demonstrate the radical formation that peaked at 3 min of reperfusion after 30 min of global ischemia. Cardiotoxic effects of DMPO can be excluded by using of the "mix-up" method (DMPO is added to effluent) because relatively high DMPO concentration (20-200 mmol/liter) is important for demonstration of free radical production
Tárgyszavak:Orvostudományok Gyógyszerészeti tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Free Radical Biology and Medicine. - 8 : 4 (1990), p. 363-372. -
További szerzők:Blasig, Ingolf E. Pali Tibor Ebert, Berndt
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
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