Effect of DL-Carnitine on Tissue Content of Adenosine Triphosphate and Creatine Phosphate in Inschaemic Myocardial Tissue

Abstract

For rhythmic myocardial contraction, high energy phosphates are supplied via efficient biochemical pathways of oxidative metabolism of substrates including carbohydrates, proteins and fats. In this study induction of ischaemia (which causes a reduction in oxygen supply and or substrate delivery) was shown to ultimately reduce the formation of the high energy phosphates (adenosine triphosphate ATP - and creatine phosphate· CP-). The ATP values were reduced to 7.2 ± 2. 7µmols/g dry weight and CP values to 6.9 ± 1.5 µmols/g dry weight for in ischaemic myocardial tissue. This contrasts with control values of 16.2 ± 5.2µmols/g dry weight for ATP and 11.7± 2.5 µmols/g dry weight for CP in normal (non ischaemic) myocardial tissue. Continuous perfusion of the hearts with perfusate containing 4.9µmols/ml DL-Carnitine appeared to prevent the lowering of ATP and CP levels as a result of induction of ischaemia. The values (14.48±2.5µmols/g dry weight for ATP and 13.1±4.0µmols/g dry "eight for CP) are significantly (P<0.05) higher than corresponding values for ischaemic myocardial tissue not per fused with DL-Carnitine (ATP 7.2±2.7µ mols/g dry weight and CP 6.9±1.5.1 µmols/g dry weight). These observations indicate that DL-Carnitine prevents the depletion (and conserves to near normal values) the content of ATP and CP m 1schaemic myocardial tissue. This finding is of potential value in the management of 1schaemic heart diseases.