The effect of beta-adrenoceptor blocking drugs on free fatty acid and glucose utilization of the isolated canine heart with normal and restricted flow in the presence and absence of noradrenaline.

Effect of adrenergic beta-receptor blockade on the myocardial utilization of the main substrates by the isolated fibrillating dog heart perfused with constant volume of blood from a donor animal was studied at normal and restricted flow, and in the presence of noradrenaline. A direct metabolic action of the beta-blockade by increasing glucose uptake in the normal and reducing it in the ischemic heart, furthermore moderating the ischemic diminution of the lactate uptake could be shown. The intervention reduced elevated serum free fatty acid level and increased myocardial free fatty acid uptake observed in the presence of noradrenaline.