Abstract
Two new chemical compounds (MY-7816 and MY-7674) induced a lipometabolic disorder in rats and dogs. The characteristic histological lesions in rats administered orally with MY-7876 or MY-7674 were cytoplasmic vacuolation in hepatic cells, Kupffer cells, convoluted tubular epithelial cells, adrenal cortical cells, and other parenchymal cells. Similar cytoplasmic vacuolation and eosinophilic cytoplasmic inclusions were observed in the hepatic cells of dogs treated with MY-7674. The cytoplasmic vacuoles in the hepatic cells of both rats and dogs examined were stained bluish black with Baker stain and consisted of myelinosomes by electron microscope. These changes were similar to those in the drug-induced lipidosis.
However, no vacuolated cells were found in the lymphoid organs, hematopoietic system, and nervous system. In general, such organs and systems were involved in the drug-induced lipidosis. These different findings caused by the present chemicals might result from a variability in the drug-distribution or concentration in the metabolizing process.
