Pharmacological preconditioning with L-carnitine: relevance to myocardial hemodynamic function and glycogen and lactate content.
Carnitine is a vital biologic substance facilitating fatty acids transport into mitochondria for ATP production. This study was to investigate the effects of pre-ischemic pharmacological preconditioning (PC) with L-carnitine (L-Car) on myocardial infarct size and cardiac functions in ischemic and reperfused isolated rat heart and meanwhile on left ventricular glycogen and lactate content. Isolated rat hearts were subjected to 30 min coronary artery occlusion followed by 120 min reperfusion. The hearts (n= 8-12) were perfused with L-Car (0.5-5 mM) only for 15 min before to 10 min after induction of ischemia. Preconditioning of the hearts with L-Car provided concentration-dependent cardioprotection as evidenced by improved postischemic ventricular functional recovery (developed pressure, left ventricular end diastolic pressure and coronary flow rate) and reduced myocardial infarct size (p<0.001). L-Car (2.5 mM) decreased both glycogen (p<0.001) and lactate (p>0.05) content in left ventricle during ischemia compared with the control. The results of this study demonstrate that L-Car pharmacologically precondition the hearts against ischemic and reperfusion injury in part by recovery of postischemic ventricular hemodynamic functions, depletion of glycogen and therefore reduction of lactate accumulation.
Najafi
Moslem
M
Department of Pharmacology, School of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
Javidnia
Ali
A
Ghorbani-Haghjo
Amir
A
Mohammadi
Sadollah
S
Garjani
Alireza
A
D000255:Adenosine Triphosphate / Q000096:biosynthesis; D000818:Animals; D002331:Carnitine / Q000494:pharmacology*; D006003:Glycogen / Q000032:analysis*; D006439:Hemodynamics / Q000187:drug effects*; D019157:Ischemic Preconditioning, Myocardial; D019344:Lactic Acid / Q000032:analysis*; D008297:Male; D017202:Myocardial Ischemia / Q000188:drug therapy / Q000503:physiopathology; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D019344:Lactic Acid; D000255:Adenosine Triphosphate; D006003:Glycogen; D002331:Carnitine