Einosuke Sakurai (1), Takehiko Maeda (2), Shuji Kaneko (3), Akinori Akaike
(2) and Masamichi Satoh (1)
Departments of (1) Molecular Pharmacology, (2) Pharmacology and (3) Neuropharmacology, Faculty of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
Abstract: We examined the effects of [Arg8]-vasopressin (AVP) on long term potentiation (LTP) of the field excitatory postsynaptic potentials at CA1 and CA3 synapses in adult guinea pig hippocampal slices. AVP (10 nM) depressed the magnitude of LTP without any effects on basal responses at both synaptic pathways. The depressive effect by AVP at CA1 synapses appears to be receptor-mediated since it was inhibited by an AVP V1-receptor antagonist, [Pmp1,Tyr (Me)2]-AVP. From these results, AVP may play an inhibitory role on the induction of LTP via V1 receptors in the guinea pig hippocampus.
Keywords: [Arg8]-vasopressin, Long term potentiation, Hippocampus