Exendin (5-39) (intracerebroventricular injection; 0.3 μg; once daily; 1-week) increases GLT-1 protein levels in the hippocampus of male Wistar rats. Additionally, hippocampal slices are prepared from Ex-treated or vehicle rats,Exendin (5-39) decreases fEPSP decay time and increases the input-output relation and decreased the paired-pulse ratio in the dentate gyrus (DG). Furthermore, Ex inhibits long-term depression but not long-term potentiation in the DG^[1]. Animal Model: Wistar rats (3 weeks old and 18 days pregnant)^[1]Dosage: 0.3 μg Administration: Intracerebroventricular injection; 0.3 μg; once daily; 1-week Result: Inhibited GLT-1 protein levels and inhibited long-term depression in rats.