pattern of distribution of dimethylbenz(a)anthracene in the Amazon molly, Poecilia formosa (Girard), after intraperitoneal injection

The present paper describes the distribution and accumulation of labelled dimethylbenz (a)anthracene (DMBA) in the Amazon molly after intraperitoneal injection. The study was made to see whether there was preferential accumulation of the compound in the spieen; the Undings showed that this was not the case. Two hours after injection, DMBA was present throughout the body, except in the brain and the ovary. There was enhanced deposition at four sites, in the macrophages of the atrium of the heart and the peritoneum, the liver and the exocrine pancreas. DMBA was taken up by reticuloendothelial macrophages for 78 h after injection, then it was lost. The accumulation and disappearance of radioactive labet seen in the liver and pancreatic cells probably represented the pattern of metabolism of the compound. By 400 h after injection there was little DMBA remaining. Label accumulated in the ameloblasts, which secrete the enamel capping of the teeth.