The cardiomyopathy of the Syrian hamster (strain BIO 8262)--hypertrophic or dystrophic?

Chemical as well as cytophotometric studies were carried out on myocardium of cardiomyopathic hamsters of strain BIO 8262 and of healthy control hamsters of strain CLAC. Our interest was to find out whether the cardiomyopathic hamsters suffer from hypertrophic cardiomyopathy or not. The heart muscle mass was only slightly increased in the older cardiomyopathic hamsters when compared with the controls. This increase was accompanied by an elevated content of total DNS, RNS and protein. Furthermore, the number of hyperdiploid heart muscle cells was slightly increased in the older diseased animals. However, all these changes were of minor degree. Thus, a distinct hypertrophying process in the myocardium of the cardiomyopathic hamsters can be excluded. On the other hand, the connective tissue components (polysaccharides and collagen) were distinctly increased in the hearts of older cardiomyopathic hamsters. This is in accordance with morphological investigations, in which replacement of necrotic myocardium by fibrosis could be detected.