Protein kinase C inhibitors block generation of anoxia-induced long-term potentiation

THE aim of this study was to study the possible intracellular mechanisms un derlying the anoxia-induced long-term potentiation (anoxic LTP) in the CA1 neurons of rat hippocampal slices using extra- and intracellular recording techniques. Superfusion of the hippocampal slices with the protein kinase C (PKC) inhibitors NPC-15437 (20 mu M) or H-7 (20 mu M) specifically prevent ed the induction of anoxic LTP. Moreover, the anoxic LTP was completely abo lished in neurons intracellularly recorded with the selective PKC inhibitor PKCI 19-36 (50 mu M). The specific cAMP-dependent protein kinase (PKA) inh ibitor Rp-cyclic adenosine 3',5'-monophosphate (Rp-cAMPS, 25 mu M) had no e ffect on the anoxic LTP. It is concluded that induction of anoxic LTP requi res the activation of postsynaptic PKC. (C) 1998 Lippincott Williams & Wilk ins.