Effects of bifemelane on incomplete cerebral ischaemia-induced reduction of long-term potentiation in rat hippocampal neurones in vivo.

In the present study, we investigated the effects of bifemelane on the reduction of hippocampal long-term potentiation after transient ischaemia. Bilateral common carotid arteries were clamped for 10 min. in halothane-anaesthetized rats. Thirty min. before occlusion, bifemelane (25 mg/kg, intraperitoneally) or saline was administered to the rats. Four days after occlusion, we measured long-term potentiation in Schaffer collateral-CA1 synapses and perforant path-dentate gyrus synapses in vivo. Long-term potentiation was significantly reduced in both the Schaffer collateral-CA1 and perforant path-dentate gyrus synapses in the saline-injected group. However bifemelane decreased the ischaemia-induced reduction of long-term potentiation in perforant path-dentate gyrus synapses, but not in Schaffer collateral-CA1 synapses. The findings suggest that bifemelane deserves further attention with regard to possible protective role in ischaemia.