Autoradiographic Evidence for Penetration of 3H-Ceftriaxone (Rocephin®) into Cells of Spleen, Liver and Kidney of Mice

Ceftriaxone (Rocephin®), a broad-spectrum parenteral cephalosporin with an exceptionally long elimination half-life, has a marked activity against both Salmonella typhimurium infections in mice and typhoid fever in man. This study investigates autoradiographically the penetration of ceftriaxone into murine cells of liver, spleen and kidney, with emphasis on the cells of the reticuloendothelial system (RES). The RES is an important site of localization of the pathogenic agent of typhoid fever. An incorporation of ceftriaxone was found in several cell types of the three investigated organs, in particular the cells of the RES and in precursors, e.g. monocytes of the blood stream, Kupffer cells or reticular cells. Besides long biological half-life, satisfactory penetration into phagocytes and other tissue cells has been shown, which is essential to the good in vivo activity of ceftriaxone against systemic Salmonella infections.