5-HT1A receptor-mediated inhibition of long-term potentiation in rat visual cortex

We investigated the effect of 8-hydroxy-2-(N,N-dipropylamino)tetralin (8-OH-DPAT), a 5-HT1A receptor agonist, on the induction of long-term potentiation in rat visual cortex slices. Perfusion of 8-OH-DPAT (0.1-10 mu M) did not affect layer II/III field potentials evoked by test stimulation of layer IV, but significantly reduced long-term potentiation induced by tetanic stimulation. The inhibitory effect of 8-OH-DPAT was blocked by the 5-HT1 receptor antagonist, pindolol (10 mu M), but not by the 5-HT2,7 receptor antagonist, ritanserin (100 mu M), nor by the 5-HT3,4 receptor antagonist, MDL72222 (100 mu M). These results suggest that the rat visual cortex long-term potentiation is inhibited by 5-HT1A receptor stimulation. (C) 1998 Elsevier Science B.V. All rights reserved.