Hepatocyte-mediated transport to the bile of AMI-HS, a particulate contrast agent

RATIONALE AND OBJECTIVES. The elimination of hepatocyte-directed particulat e contrast agents has not been studied in the same detail as particles elim inated mainly by the mononuclear phagocyte system. The aim of the present s tudy was to elucidate the fate of these particles by a multidisciplinary ap proach. METHODS. After intravenous injection of AMI-HS particles directed to the he patocytes, rats were killed and cytological studies, by both electron micro scopy and histochemistry, and spectroscopic studies of the bile were perfor med. The data were compared with a dynamic magnetic resonance study of the heart and liver. RESULTS. The particles were rapidly cleared from the blood by Kupffer cells and hepatocytes and then found first in the vascular and later in the bili ary pole of the hepatocytes. After 24 hours, a relaxometric characterizatio n of the bile showed the presence of unchanged particles in the bile. CONCLUSIONS. These results show the capacity of the liver to excrete unchan ged AMI-HS particles directly into the bile.