FOCAL ELLIPSOID DEPOSITS IN THE ATRIAL MYOCYTES OF SYRIAN-HAMSTER

A peculiar hyaline sarcoplasmic inclusion in the atrial myocytes of ol d female Syrian hamsters is described. This type of inclusion resemble s that described in rare human cardiomyopathy. They have also been des cribed in other rodents and have been speculated eventually to contain atrial natriuretic factor (ANF). The present study demonstrated that they are fibrillar in nature, however, and do not contain ANF-immunore active product. Because their morphologic aspect is analogous to that described in human heart and in the pathology of other contractile tis sues, it is suggested that they probably consist of intermediate filam ents and/or associated macromolecules.