L-CARNITINE AND COENZYME-Q(10) PROTECTIVE ACTION AGAINST ISCHEMIA ANDREPERFUSION OF WORKING RAT-HEART

The protective effect of L-carnitine, coenzyme Q10 and their combinati on on haemodynamic and metabolic variables has been investigated in is olated perfused working rat hearts after 10 min of global normothermic ischaemia followed by 60 min of reperfusion. In untreated rats or in rats treated only with L-carnitine or with coenzyme Q10, this experime ntal condition did not induce any irreversible myocardial injury as me asured by leakage of cardiac enzymes; however, it decreased some haemo dynamic parameters such as cardiac output and minute work, as well as the ATP concentration and the total adenine nucleotide pool. No variat ions in haemodynamic and metabolic parameters were observed in the rat s treated with L-carnitine plus coenzyme Q10. In the perfusate of the hearts of the rats treated with both compounds, a lower purine release (a good index of myocardial energy balance) was also obtained. Althou gh the molecular mechanisms remain to be defined, it appears that the association of L-carnitine and coenzyme Q10 is more effective than usi ng these compounds separately. The complementary and synergic actions of L-carnitine and coenzyme Q10 on metabolism and against peroxidation by oxygen reaction species may explain the efficacy of their associat ion.