Differential effects of phospholipase inhibitors in long-term potentiation in the rat hippocampal mossy fiber synapses and Schaffer/commissural synapses.
Bath application of the inhibitors of phospholipases, nordihydroguaiaretic acid (NDGA) and p-bromo-phenacyl bromide (BPB), to the rat hippocampal slices suppressed long-term potentiation (LTP) in Schaffer/commissural-CA1 pyramidal synapses. On the other hand, neither of the two inhibitors suppressed LTP in mossy fiber-CA3 pyramidal cell synapses. BPB did not suppress phosphatidylinositol-specific phospholipase C (PI-PLC) activity of the slices. These results suggested that the mechanisms of LTP were quite different in the CA1 and CA3 subfields of rat hippocampus: in CA1, the involvement of an arachidonate metabolism was strongly suggested, whereas in CA3, an arachidonic acid cascade may not be necessary for LTP.
National Institute for Physiological Sciences, Department of Cellular Physiology, Okazaki, Japan.
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Okada
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Yamagishi
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Sugiyama
D000098:Acetophenones / Q000494:pharmacology*; D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002396:Catechols / Q000494:pharmacology*; D004558:Electric Stimulation; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D066298:In Vitro Techniques; D009637:Masoprocol / Q000494:pharmacology*; D010740:Phospholipases / Q000502:physiology*; D051381:Rats
D000098:Acetophenones; D002396:Catechols; D004791:Enzyme Inhibitors; D009637:Masoprocol; D010740:Phospholipases; C006821:4-bromophenacyl bromide