There was examined the function of NAD- and NADP-dependent malate dehydrogenases (MDG) of myocardium and skeletal muscles of laboratory animals. The activity of NAD-MDG in oxaloacetate-malate direction were higher in the myocardial cytoplasm and skeletal muscles than in mitochondries of those tissues. The NADP-MDG activity, contents of metabolites CTA malate and oxaloocetate, adeniles nucleotides exceed similar indices of skeletal muscles, which is an evidence of advantages of protons transport to the myocardial mitochondria matrix as compared with skeletal muscles. In the blood the NAD-MGD activity is represented by cytoplasmatic enzyme forms.
