Accumulation and Retention of Mercury in the Mouse

Abstract
The distribution of Hg after a single intravenous injection of radioactively labeled phenylmercuric acetate in mice was studied by autoradiography of whole-body sagittal sections. The order of isotope concentration in the organs was determined by densitometric comparison with the autoradiogram of a standard isotope "staircase" attached to each section. The findings were compared with those of a previous study in which the same dose of Hg was given as HgCl2. Several differences were found. In the present study, accumulation in the liver and in the intestines was more pronounced the first hours and days after injection, indicating that more Hg is excreted in the alimentary tract after injection of the phenylmercuric complex. Greater uptake and retention of Hg was also found in the muscles but less uptake in the renal cortex, bone marrow, and spleen than after injection of inorganic Hg. The autoradiographic observations are consistent with a breakdown in the body of the phenylmercuric radical to inorganic Hg.