A light and electron microscopic study of osteodentin formation in the rat incisor after adriamycin administration.

The effect of adriamycin (10 mg/kg body weight) on the rat incisor was investigated in 8-day-old animals at 9 days and 14 days after subcutaneous injection. The drug produced changes that were still present 14 days after administration. During this time osteodentin formation, which appeared to be the principal effect of the drug on the incisors, occurred to such an extent that in some regions of the teeth the pulp chamber was almost completely occluded. The formation of osteodentin began at the periphery of the pulp and gradually advanced towards the central region. Moreover, in some sections of the incisor the dentin layer was greatly reduced to a thin superficial layer, while osteodentin surrounded most of the pulp chamber. Cells that appeared to be differentiated pulp-mesenchymal cells were found within as well as on the surface of the irregular osteodentin matrix. Since this drug has been used in the treatment of childhood osteosarcomas, the possibility of dental abnormalities developing in these children cannot be overlooked.

Neuronal loss from cervical dorsal root ganglia in adriamycin induced peripheral neuropathy--a quantitative study.

The neurotoxic effects of some of the more recent chemotherapeutic drugs are not well studied. Adriamycin is such a drug, used in the treatment of some cancers in both children and adults. An examination of its effects on the peripheral nervous system was therefore undertaken particularly in view of its use in children. Sprague-Dawley rats, 1 week of age, were injected with a subcutaneous injection of adriamycin (10 mg/kg/wt.). Cervical dorsal root ganglia were removed and prepared for quantitative study at the light microscopic level. Quantitative analysis of neuronal counts of the ganglia showed a statistically significant loss (P less than 0.001) of sensory neurons in the treated rats. The remaining neurons displayed many abnormal morphological features suggestive of a degenerative process. From this study, functional loss cannot be correlated to neuronal type but the significant loss of neurons and numbers of affected cells observed would have a serious effect on sensory function.