An ultrastructural study of methionine sulphoximine-induced glycogen accumulation in astrocytes of the mouse cerebral cortex.

Glycogen distribution in the mouse cerebral cortex was examined with electron microscopy following treatment with the experimental convulsant, methionine sulphoximine (M.S.O.). Both at 24 and 48 h followed administration of M.S.O., accumulation of particulate glycogen was prominent in astrocytes throughout the cerebral cortex. In astrocyte cell bodies and in subpial, pericapillary and perineuronal astrocyte processes the glycogen often completely filled the cytoplasm, crowding the remaining organelles and inclusions. The present findings correlate well with biochemical studies of M.S.O. effects of glutamine synthetase activity and energy metabolism. It is suggested that the glycogen may be derived from glutamate which under normal conditions would be converted to glutamine.