| Abstract: | Autoradiographic examinations of the heart muscle in experimental myocardial necroses using 3H-thymidine, revealed a high DNA synthesis in the connective tissue cells in the zone of necrosis in the acute period of infarction and its subsequent decrease. Deviations from this regularity were observed when relapses of necrosis developed. The activation of DNA synthesis occurred to a lesser extent in stromal cells of the periinfarction and remote zones of the heart. Muscle cells incorporated 3H-thymidine extremely rarely. When myocardial infarction was combined with aterosclerosis, relapses of necrosis occurred frequently, and morphological changes in many arteries and veins were accompanied by 3H-thymidine incorporation into the nuclei of the endothelium, smooth cells and adventitial cells. Inhibition of DNA synthesis in connective tissue cells of various heart zones was observed in cases of combined myocardial infarction and aterosclerosis and hypertension. |
