50 mg acetyl-choline in 500 cc isotonic saline were injected 110,000 intravenously into unanesthetized dogs during a 90 min. period daily until death of dog. Fatal coronary artery and myocardial damage occurred in 25-226 days; the older the dog, the faster the effect. There occurred typical electrocardiogram changes, hyaline degeneration of myocardium, in younger animals melena and hematemesis; changes which were similar to actual ligation of coronary artery and to clinical coronary disease. Animals dying of adrenal insufficiency either experimentally or clinically showed cardiac lesions and ulcers of the duodenum and stomach. A medial change with calcareous deposits also occurred in peripheral vessels.