EFFECTS OF ENDOTHELIN-1 ON HIPPOCAMPAL SYNAPTIC PLASTICITY

WE examined the effects of puff application of endothelin (ET)-1 on th e induction of long-term potentiation (LTP) and heterosynaptic long-te rm depression (LTD) in hippocampal CA1 slices. ET-1 applied 2 min prio r to tetanus blocked the induction of LTP, but facilitated the inducti on of heterosynaptic LTD. These ET-1 effects on synaptic plasticity we re dose-dependent, and not due to a generalized depression of baseline responses. ET-1 did not alter NMDA receptor-mediated responses. These data provide the first evidence that endothelin modulates activity-de pendent synaptic plasticity, and the potency of these effects suggests that endogenous ET-1 may play an important role in regulating memory storage processes. (C) 1998 Rapid Science Ltd.