Morphological studies of cultured swine aorta media explants.

Abstract

Expiants obtained from the media of swine abdominal aortas, free of intimai cells and of vasa vasis, were cultivated in a semisynthetic medium for various periods of time, up to 50 days. Under these conditions it was observed that some smooth muscle cells, apparently independently from their location, undergo dedifferentiation, become rich in organelles, migrate and possibly multiply. These cells, found outside the original expiant, are capable of synthesis of collagen and elastic substance. Other cells seem unable to become activated and after some time die. It is suggested that cells capable of dedifferentiation “in vitro” may be the same that “in vivo” under adequate stimulation are responsible for proliferative atherosclerotic lesions.