Abstract
MIR, the first available experimental models, are prone to develop ischemic heart disease spontaneously, and they can be regarded as an animal model for scattered-type of myocardial infarction. In this study, histo-pathological examination of MIR which were fed normal diet and died naturally, revealed systemic vascular changes including coronary arteries frequently asso-ciated with thrombosis. These histological findings were also noted in some cases of SHRSP from which MIR was derived, but vascural obstructive changes in general appeared to be dominant in MIR, in which some additional factors related to thrombosis were supposed to be involved. Moreover, alterations in coronary arteries were more marked in MIR than in SHRSP which died mainly from stroke without severe myocardial lesions. Therefore, it can be concluded that MIR is a useful animal model for studying mechanisms and prevention of coronary heart diseases.
