AGE-DEPENDENT CHANGES IN COLLAGEN-METABOLISM AND RESPONSE TO HYPERTONIC CULTURE CONDITIONS OF RAT AORTIC SMOOTH-MUSCLE CELLS AND SKIN FIBROBLASTS

The rates of growth and collagen synthesis of rat aortic smooth muscle cells in culture were decreased with increasing the age of the animals from which the cells were obtained. These rates were further decreased by the presence of a 0.1 M excess concentration of KCl in the culture medium, and the cells obtained from older animals were much more sensitive to the inhibitory effect of the hypertonic culture condition. These tendencies were observed in smooth muscle cells obtained from different phases of in vitro cellular aging and also in skin fibroblasts obtained from animals of different ages. These results indicate that the cells become more sensitive to the environmental changes with increasing age both in vivo and in vitro. © 1990.