Degenerative Changes in the Cardiovascular System of the Spawning Pacific Salmon ( Oncorhynchus tshawytscha )

Abstract

In a stndy of the cardiovascular system of spawning Pacific salmon, degenerative changes were found in the heart muscle, coronary and visceral arteries, and capillaries of the kidney glomeruli. The heart muscle showed vacuolization of the muscle fibers with loss of fibrils, deposition of collagen, and cartilaginous meta plasia. Changes in the coronary and visceral arteries consisted of intimal hyperplasia with deposition of mucopolysaccharides, disruption of the internal elastic membrane, and destruction of adjacent muscle fibers in the media. The glomerular capillaries showed marked sclerosis. The resemblance of the arterial changes in the salmon to the beginning mani festations of arteriosclerosis in man, mammals, and birds is pointed out, and the relationship of the salmon's state of hyperadrenoeorticism to the occurrence of the vascular lesions is discussed.