CERIUM STIMULATES PROTEIN-BIOSYNTHESIS IN RAT-HEART IN-VIVO

The aim of the study was to ascertain whether Ce, a lanthanide that ha s been implicated in the pathogenesis of tropical endomyocardial fibro sis, interferes with the biosynthetic repertoire of the cardiac muscle in vivo. Female Sprague-Dawley rats received Ce chloride iv at 1.3 mg /kg body wt.; controls received an equal volume of physiological salin e. Rates of protein synthesis and transcription in cardiac muscle, mea sured in terms of incorporation of (H-3)-phenylalanine and (H-3)-uridi ne, respectively, into trichloroacetic acid-insoluble material were fo und to be significantly higher in Ce-treated animals. As low levels of Ce were earlier shown to stimulate collagen as well as noncollagen pr otein synthesis in cardiac fibroblasts in vitro, the stimulatory effec t of the element in vivo reported here supports the speculation that i t may influence the expression of proteins Like collagen in the heart and contribute to their accumulation as in endomyocardial fibrosis.