The dynamics of the content of insulin, somatotropic hormone, glucose and the free fatty acids were studied in 32 male patients with ischaemic heart disease subjected to direct revascularization on the myocardium under neuroleptanalgesia and artificial circulation with moderate hypothermia and haemodilution. It is established that during operations on the coronaries under these conditions insulin secretion is not depressed, despite stable increase of the somatotropic hormone in the blood. High concentrations of glucose and insulin in the blood prevent the rise of the free fatty acids.