Presently, there is growing interest in studying the activity of the sympathoadrenal system in the aging process of the body and the development of diseases of the cardiovascular system associated with age. The intention of the research is evaluation of β-adrenoreactivity of erythrocyte membranes (β-ARM) of intact rats and rats with postinfarction cardiosclerosis at the age of 4, 12 and 24 months: the first group contained twenty 4 months old animals; the second group - twenty 12 months old animals; the third group - twenty 24 months old animals. In the each group were distinguish 10 intact rats and 10 experimental rats, that have postinfarction cardiosclerosis (PICS) modeled by coronary occlusion. The experiments was completed on 60 male-rats. It was shown, that in intact animals the indicator of β-ARM significantly decreases by 12 months in relation to the group of 4 monthly animals. In the groups of intact animals of 12 and 24 months, there were no significant differences in β-ARM. The severity of cardiac hypertrophy in animals with PICS was inversely related to age - 4>12>24 months old. Formed PICS in animals aged 4 and 12 months was accompanied by a expressed increase of β-ARM, in animals 24 months with PICS β-ARM did not significantly change. Changes in the β-ARM index characterizing the state of the CAS receptor link under PICS conditions are age-related, in adults 12 months of age with PICS, an increase in β-ARM relative to the parameter at 4 months. animals indicates compensatory desensitization of β-adrenergic receptors upon activation of CAS in response to the development of contractile myocardial insufficiency. In the age group of 24 months with the formed cardiosclerosis, compensatory activation of CAS is manifested to a lesser extent.