Cobalt-induced experimental epilepsy in cats pharmacologically immunodepressed. An EEG and histological study.

The authors made 11 adult cats epileptic by implanting cobalt powder on the left sensorimotor cortex. Some of the animals were treated with the immunodepressant drug, cyclophosphamide (Endoxan), before and after surgery, and others were not. Then the two groups of animals were compared in terms of EEG and histopathological findings. The treatedanimals showed a definite reduction of focal electrical activity both primary and secondary, and a much milder perifocal parvicellular infiltration and cerebral edema. In view of these findings, the authors suggest that in addition to other well-known factors, the pathogenesis of cobalt-induced experimental epilepsy involves immunological mechanisms triggered by the release of nerve tissue antigens as a result of tissue injury caused by cobalt. This would result in the formation of antibodies directed against several brain constituents. Last, the authors submit that a similar autoimmune mechanism may be at play also in the pathogenesis of some forms of focal epilepsy of traumatic origin.