Publications (2)5.88 Total impact
-
Article: Hemin, inducer of heme-oxygenase 1, improves functional recovery from myocardial stunning in conscious dogs.
[show abstract] [hide abstract]
ABSTRACT: To examine the effects of pretreatment with hemin, an inducer of the potential antioxidative enzyme heme-oxygenase 1 (HO-1) or heat-shock protein 32, on myocardial stunning. Randomized animal study. Animal laboratory of a university hospital. Chronically instrumented mongrel dogs (n = 44). Dogs underwent chronic instrumentation for measurement of hemodynamics and myocardial wall thickening fraction (WTF). Experiments with 12 dogs were performed on separate days in a crossover fashion: (1) 10 minutes of left anterior descending (LAD) coronary artery occlusion after application of hemin (9 mg/kg/d) for 1 week and (2) 10 minutes of LAD coronary artery occlusion without hemin pretreatment. In control experiments (n = 32), the reversible induction of HO-1, using gel electrophoresis and Western blotting, was determined. WTF was measured as a baseline value before hemin administration and at predetermined time points until complete recovery from stunning. LAD artery occlusion caused a significant reduction in the WTF in the LAD-perfused area with and without hemin, without significant hemodynamic changes. At all time points, after 1 minute of reperfusion, the WTF as percentage of baseline values was significantly higher after hemin pretreatment (p < 0.05). Baseline WTF values were reached after 24 hours with and after >48 hours without hemin pretreatment (p < 0.05). Hemin pretreatment attenuates myocardial stunning in conscious dogs.Journal of Cardiothoracic and Vascular Anesthesia 08/2001; 15(4):422-7. · 1.64 Impact Factor -
Article: Naloxone improves functional recovery of myocardial stunning in conscious dogs through its action on the central nervous system.
[show abstract] [hide abstract]
ABSTRACT: This study tests the hypothesis that naloxone, but not its quarternary salt, naloxone methiodide (which does not enter the central nervous system), improves recovery from myocardial stunning in conscious dogs. Twenty dogs were chronically instrumented for measurement of heart rate, left atrial, aortic and left ventricular pressure (LVP), LV dP x dtmax(-1) and myocardial wall thickening fraction (WTF). Regional myocardial blood flow was determined with coloured microspheres. Occluder around the left anterior descending artery (LAD) allowed induction of reversible LAD ischaemia. Each of the 20 dogs underwent two LAD ischaemic challenges. Experiments (performed on separate days, in crossover fashion) were: (i) 10 min of LAD occlusion after application of naloxone 63 microg kg(-1) or naloxone methiodide 63 microg kg(-1) and (ii) occlusion without naloxone or naloxone methiodide. WTF was measured at baseline and until complete recovery occurred. LAD ischaemia significantly reduced LAD WTF with (mean (SD) 54 (15)% lower than baseline) and without naloxone (55 (16)% lower than baseline), without significant haemodynamic differences. Between I to 30 min of reperfusion, WTF was significantly higher with naloxone (P < 0.05). There was no difference in WTF with or without naloxone methiodide. We conclude that naloxone improved recovery from myocardial stunning in conscious dogs, and that this was centrally mediated.BJA British Journal of Anaesthesia 04/2001; 86(4):545-9. · 4.24 Impact Factor
