Proliferation of primary cultures from rat aortic media. Effects of hyperlipemic serum.

Tissue cultures have been made from explants of thoracic aortas to study the growth pattern of rat aortic mediacytes. Three parameters were measured weekly: the surface of the culture, the relative increase of this surface and the number of 3H-thymidine labelled cells per unit surface. The primary cultures showed two distinctive phases: a first phase with continuous growth followed by a plateau phase. We studied the growth effect of homologous hypercholesterolemic serum added to the cultures. The cell proliferation was affected by the cholesterol level in the medium and the stage of the culture at which serum incubation was initiated. An enhancing effect occurred in the rat resistant to such treatment in vivo.