In vivo chronic carvedilol treatment in rats attenuates ex vivo regional infarction of the heart.
OBJECTIVE
Carvedilol is an alpha-and beta-blocking agent with antioxidant properties. We examined if treatment with carvedilol in vivo protected the heart against ischemic injury ex vivo.


METHODS
Isolated hearts from treated rats (80 mg/kg/day) were subjected to 30 min regional ischemia. Hearts from non-treated animals received either no drug, 10 min carvedilol (1 microM) acute or ischemic preconditioning (IP) by 5 min ischemia +5 min reperfusion prior to regional ischemia. In separate experiments isolated hearts were subjected to 15 min global ischemia and 30 min reperfusion.


RESULTS
Infarct size was significantly reduced by ischemic preconditioning or by chronic carvedilol treatment (9.0+/-0.9% and 7.2+/-1.9% of risk zone infarcted, respectively, vs. 33.8+/-6.4% in control hearts, mean+/-SEM, p < 0.05). Recovery of left ventricular developed pressure after global ischemia was not improved by carvedilol. Post-ischemic rise in left ventricular end diastolic pressure was, however, attenuated by chronic carvedilol treatment.


CONCLUSIONS
Chronic in vivo but not acute ex vivo pretreatment with carvedilol significantly limited infarct size in isolated rat hearts.
Starkopf
Joel
J
Department of Biochemistry, Department of Anaesthesiology and Intensive Care, University of Tartu, Tartu, Estonia.
Hegna
Stig
S
Johansen
Odd Erik
OE
Munch-Ellingsen
Jens
J
Mjøs
Ole D
OD
Ytrehus
Kirsti
K
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D002227:Carbazoles / Q000494:pharmacology*; D000077261:Carvedilol; D003971:Diastole / Q000187:drug effects; D019157:Ischemic Preconditioning, Myocardial; D023421:Models, Animal; D009203:Myocardial Infarction / Q000517:prevention & control; D015428:Myocardial Reperfusion Injury / Q000188:drug therapy*; D017682:Myocardial Stunning / Q000188:drug therapy*; D011412:Propanolamines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D000317:Adrenergic alpha-Antagonists; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol