EFFECT OF SOMATOSTATIN AND GABA ON LONG-TERM POTENTIATION IN HIPPOCAMPAL CA1 AREA IN RATS

AIM: To study the effect of somatostatin (SS) and GABA on the long-term potentiation (LTP) of hippocampal CA1 area in rats. METHODS: Active avoidance response (AAR) of shuttle-box was recorded and population spikes (PS) were taken as indices of LTP. RESULTS: Increased percentages of PSA (PS amplitude, in AAR-acquired rats are more than 100 %; After intrahippocampal injection (ih) of SS (1 g L(-1)), increased percentages of PSA exhibited above 120 %. Increased percentages of PSA were significantly decreased (<10 %, n = 3) and even caused no PS (n = 8) by ih cysteamine (Cys, 20 g L(-1), the depletor of SS); ih GABA (200 g L(-1)) indicated that the increased percentages of PSA are less than 30 %, GABA weakened the effect of SS on LTP. CONCLUSION: SS enhance hippocampal LTP but GABA decrease it; they may influence each other to regulate the hippocampal synaptic transmission in the process of learning and memory.