AUTORADIOGRAPHIC STUDIES OF SYNTHESIS OF DNA COLLAGEN AND MUCOPOLYSACCHARIDES IN EXPERIMENTALLY-INDUCED PROLIFERATION OF AORTIC INTIMA

The development of obliterating endangiopathy in double stenosed aorta abdominalis of the rat was investigated histologically and autoradlographically. Intima cell proliferations which narrowed the vessel lumen were observed in 69% of the operated rats. Twenty-four hours post-operative the 1st DNA-synthesizing cells could be observed at the level of endothelial cells by means of 3H-thymidine. The maximum of intima cell proliferation was demonstrated at the 7th day as determined by the 3H-thymidine-index. At this time the output of 3H-proline-marked material from the proliferated intima cells could be shown by varying the intervals between administration of radioactive amino acid and sacrifice of the experimental animals. A considerable incorporation of 35s-sulfate in proliferating cells was measured photometrically. The origin of these cells and their role in the beginning synthesis of collage nous fibers and in production of sul-fated mucopolysaccharides were discussed.