Fig. 8

Schematic representation of astroglial alterations induced by Li-pilocarpine (at 56 days) and prevented by dexamethasone. We postulate that the Li-pilocarpine insult causes an inflammatory and astroglial injury. Dexamethasone (administered 24 h after pilocarpine) was able to prevent such alterations partially. Neuronal activity released K⁺, which is buffered by astroglial activity. GFAP, S100B, and GS expressions are sensitive to dexamethasone. The reduction in S100B secretion in the high-K⁺ medium was not observed in the hippocampal slices from Li-pilocarpine-treated animals. ~, ↑, and ↓ signify unchanged, increased, and decreased, respectively, caused by Li-pilocarpine administration; √ and X refer to the prevention or non-prevention, respectively, by dexamethasone (DEX)