Immunohistochemical investigations in experimentally induced tumors of the nervous system.

35 tumors of brain, spinal cord and cranial and peripheral nerves were induced with ENU (ethyl-nitrosourea) in the offspring of treated BD-IX pregnant rats. 36 tumors--35 of the nervous system, one nephroblastoma--were observed in 14 rats. With these results, the number of experimental nervous system tumors of the own collection induced in BD-IX rats and classified next to the rules of human neurooncology, amounts to 2,216. All 35 tumors of the nervous system were treated by a panel of immunohistochemical reactions comprising antibodies against cytoskeleton intermediary filaments such as GFAP (glial fibrillary acid protein), neurofilament proteins, vimentin and cytokeratins and some nervous system antigens such as NSE (neuron specific enolase), MBP (myelin basic protein) and S-100 protein. In central tumors, considered to be malignant gliomas, focal reactivity against vimentin and GFAP was found. Expression of other tested markers was weak or absent. In neurinoma of trigeminal and peripheral nerves, reactivity to S-100 antigen was lacking, whilst there was strong reaction to the vimentin antigen.