The lipolysis in the adipose tissue obtained from adrenalectomized and intact rats with spontaneous and renal hypertension and from rats of corresponding control groups was studied. Lypolysis under the effect of epinephrine and without it was evaluated by the concentration of nonesterified fatty acids in the tissue and by glycerine release into the incubation medium (in vitro). Reaction of the adipose tissue in response to epinephrine was the same in hypertensive and control rats when the adrenal glands were intact. Preliminary adrenalectomy which eliminated the corticosteroid action reduced the epinephrine lypolysis in the adipose tissue in control normotensive rats, but not in hypertensive rats ("facilitation" of catecholamine action on the lypolysis mechanism). This phenomenon is regarded by the authors as the alteration of plasmatic membranes adipocytes function in hypertensive animals. The adrenal cortex hypertrophy and the enhanced corticosteroid secretion in the types of hypertension studied are therefore considered as the measure for compensation of disturbances of the cell plasmatic membranes function in the internal environment tissues.