Neuron-like physiological properties of cells from human oligodendroglial tumors.

One of the most common symptoms of patients with oligodendrogliomas is the high frequency of epileptic seizures. We thus studied the physiological properties of cells in six human oligodendrogliomas and two oligoastrocytomas obtained from surgical material. The majority of tumor cells in living brain slices can generate action potentials as recorded with the patch-clamp technique indicating that this tissue is dominated by electrically excitable cells. In cultures from the same material, the action potential generating cells prevail within the first days and are subsequently replaced by electrically inexcitable cells. From histopathological and immunohistochemical data, the histogenesis of human oligodendroglial tumor is still uncertain. Our physiological study has not settled the debate on the origin of these tumors but revealed important findings with regard to this question. Since action potential generating glial cells have not been described in situ so far their occurrence in oligodendroglial tumors implies that oligodendroglial tumor cells may belong to the neuronal cell lineage.