LINOLEIC-ACID METABOLISM IN PRIMARY CULTURES OF ADULT-RAT CARDIOMYOCYTES IS IMPAIRED BY AGING

Many of the changes that occur ia the rat cardiac muscle with advancin g age are related to modifications in membrane fatty acid composition, polyunsaturated fatty acids decreasing and saturated increasing as th e animal develops. In the present study, using cultured adult cardiomy ocytes isolated from the hearts of rats of a broad (1-24 months) age r ange, we demonstrated that the modifications in the fatty acid pattern of cardiomyocytes have to be related to alterations in the mechanism of desaturation/elongation of essential fatty acids. In fact, independ ent of the age of the animal, heart cells in culture were capable of r apidly metabolizing radiolabeled linoleic acid taken up from the surro unding medium, but to a different extent. The ability of heart cells t o metabolize linoleic acid to higher and more unsaturated metabolites decreased with the animal's age. As the age of the animal increased, t he pattern of fatty acids of the cultured cardiomyocytes showed a grad ual but significant shift, similar to those reported in the whole hear t. Data here reported confirm that the basic aging-related process in the cellular model system may also be relevant to aging in the whole a nimal. (C) 1997 Academic Press.