Ultrastructural study of moniliformin induced lesions of myocardium in rats and mice.

Effects of moniliformin on the ultrastructure of the myocardium of mice and rats were studied. Mice were given moniliformin orally at a dose of 29.46 mg.kg-1 the LD50. One h after dosing, lesions of the mitochondria of the myocardial cells were found which became more severe in 2 and 3 h. Ultrastructural lesions were also observed in the myofibrils and sarcolemma. Rats were given moniliformin orally at the dosage of 6 mg.kg-1 once daily for 56 d. Lesions of mitochondria and myofibrils were relatively mild. In the myocardiac specimens taken from the 21d post-toxin administration, lesions of the sarcolemma became more obvious. These moniliformin-induced lesions were similar to the ultrastructural changes in the myocardium of patients with Keshan disease. Our findings indicate that there may be a close and important relationship between moniliformin intoxication and Keshan disease.