Relations between reperfusion arrhythmias and myocardial norepinephrine and accumulation of calcium in the rat.
The relation between myocardial norepinephrine and reperfusion arrhythmias was examined in isolated rat hearts. The influence of pre-treatment with reserpine on the incidence of reperfusion arrhythmias and on the accumulation of calcium in the myocardium during ischemia and reperfusion was also studied. Ischemia was induced by ligation of the coronary artery and, in some experiments, the cardiac stores of norepinephrine were labeled with 3H-norepinephrine. Reperfusion after an ischemic period of 10 or 15 minutes induced a marked release of radioactivity and reperfusion arrhythmias. The radioactivity liberated after ischemia appeared to have been trapped during ischemia and washed out during reperfusion. Pre-treatment of the hearts with 0.1 mg/kg reserpine 24 hours before the experiment protected against reperfusion arrhythmias and significantly reduced the accumulation of calcium during reperfusion. The results confirm that the nature of reperfusion arrhythmias is highly dependent upon the duration of the ischemic period and sympathetic activity.
Dimassi
N
N
Facultés de Medicine et Pharmacie, Dijon, France.
Bril
A
A
Autissier
N
N
Bralet
J
J
Rochette
L
L
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000517:prevention & control; D002118:Calcium / Q000378:metabolism*; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000209:etiology* / Q000517:prevention & control; D009206:Myocardium / Q000737:chemistry*; D009638:Norepinephrine / Q000378:metabolism*; D011292:Premedication; D051381:Rats; D011919:Rats, Inbred Strains; D012110:Reserpine / Q000627:therapeutic use*; D013997:Time Factors
D012110:Reserpine; D002118:Calcium; D009638:Norepinephrine