摘要：The heterocyclic aromatic amine 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) is a potent hepatocarcinogen in cynomolgus and rhesus monkeys. The finding of high cardiac IQ-DNA adduct levels prompted a histopathological study of perfusion-fixed hearts from 10 tumor-bearing monkeys chronically dosed with IQ at 10 mg/kg or 20 mg/kg 5 days per week for 48-80 months. Two monkeys dosed only with the vehicle for IQ, hydroxypropylcellulose, served as controls. All the monkeys had normal heart weights, and no abnormalities were observed upon gross inspection of the hearts. Microscopically, focal myocardial lesions were observed in 8 of 10 monkeys dosed with IQ. Light microscopic abnormalities included myocyte necrosis with or without chronic inflammatory infiltrates, interstitial fibrosis with myocyte hypertrophy or atrophy, and vasculitis. Electron microscopic findings included disruption of the mitochondrial architecture (i.e., mitochondrial swelling and clearing of matrix densities), myofibrillar loss, disorganization of the normal alignment of sarcomeres, and occasional myocytes showing nuclear hypertrophy or peripheral clumping of the nuclear chromatin. There was some correlation between the cumulative dose of IQ and the extent of the myocardial abnormalities. These findings suggest that chronic exposure to IQ can lead to myocardial damage in monkeys. Although focal and not associated with clinical evidence of heart failure, these abnormalities may represent the initial stages of IQ-induced toxic cardiomyopathy. Full text Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (3.0M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References . 194 195 196 197 198 199
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