Effects of cAMP simulate a late stage of LTP in hippocampal CA1 neurons.

Hippocampal long-term potentiation (LTP) is thought to serve as an elementary mechanism for the establishment of certain forms of explicit memory in the mammalian brain. As is the case with behavioral memory, LTP in the CA1 region has stages: a short-term early potentiation lasting 1 to 3 hours, which is independent of protein synthesis, precedes a later, longer lasting stage (L-LTP), which requires protein synthesis. Inhibitors of cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA) blocked L-LTP, and analogs of cAMP induced a potentiation that blocked naturally induced L-LTP. The action of the cAMP analog was blocked by inhibitors of protein synthesis. Thus, activation of PKA may be a component of the mechanism that generates L-LTP.

[1]  Joseph F. Williams.  Annual Review of Pharmacology , 1975 .

[2]  H. Matthies,et al.  Two sensitive periods for the amnesic effect of anisomycin , 1980, Pharmacology Biochemistry and Behavior.

[3]  L R Squire,et al.  The pharmacology of memory: a neurobiological perspective. , 1981, Annual review of pharmacology and toxicology.

[4]  M. Krug,et al.  Anisomycin blocks the late phase of long-term potentiation in the dentate gyrus of freely moving rats , 1984, Brain Research Bulletin.

[5]  J. Sarvey,et al.  The effect of high-frequency electrical stimulation and norepinephrine on cyclic AMP levels in normal versus norepinephrine-depleted rat hippocampal slices , 1985, Brain Research.

[6]  Klaus G. Reymann,et al.  The duration of long-term potentiation in the CA1 region of the hippocampal slice preparation , 1985, Brain Research Bulletin.

[7]  E R Kandel,et al.  A critical period for macromolecular synthesis in long-term heterosynaptic facilitation in Aplysia. , 1986, Science.

[8]  Aryeh Routtenberg,et al.  Protein kinase C inhibitors eliminate hippocampal long-term potentiation , 1987, Brain Research.

[9]  U. Frey,et al.  Anisomycin, an inhibitor of protein synthesis, blocks late phases of LTP phenomena in the hippocampal CA1 region in vitro , 1988, Brain Research.

[10]  H. Matthies.  Neurobiological aspects of learning and memory. , 1989, Annual review of psychology.

[11]  W. Abraham,et al.  Inhibition of protein synthesis in the dentate gyrus, but not the entorhinal cortex, blocks maintenance of long-term potentiation in rats , 1989, Neuroscience Letters.

[12]  E R Kandel,et al.  Ca2+/calmodulin sensitivity may be common to all forms of neural adenylate cyclase. , 1989, Proceedings of the National Academy of Sciences of the United States of America.

[13]  R. Nicoll,et al.  An essential role for postsynaptic calmodulin and protein kinase activity in long-term potentiation , 1989, Nature.

[14]  U. Frey,et al.  Dopaminergic antagonists prevent long-term maintenance of posttetanic LTP in the CA1 region of rat hippocampal slices , 1990, Brain Research.

[15]  Susan R. George,et al.  Cloning of the gene for a human dopamine D5 receptor with higher affinity for dopamine than D1 , 1991, Nature.

[16]  A. Grace.  Phasic versus tonic dopamine release and the modulation of dopamine system responsivity: A hypothesis for the etiology of schizophrenia , 1991, Neuroscience.

[17]  A. Ameri,et al.  Adenosine A1 and non-A1 receptors: Intracellular analysis of the actions of adenosine agonists and antagonists in rat hippocampal neurones , 1991, Brain Research.

[18]  U. Frey,et al.  The effect of dopaminergic D1 receptor blockade during tetanization on the expression of long-term potentiation in the rat CA1 region in vitro , 1991, Neuroscience Letters.

[19]  D. Johnston,et al.  N-methyl-D-aspartate receptor activation increases cAMP levels and voltage-gated Ca2+ channel activity in area CA1 of hippocampus. , 1991, Proceedings of the National Academy of Sciences of the United States of America.

[20]  P. Greengard,et al.  Enhancement of the glutamate response by cAMP-dependent protein kinase in hippocampal neurons , 1991, Science.

[21]  E. Kandel,et al.  Long-term potentiation in the hippocampus is blocked by tyrosine kinase inhibitors , 1991, Nature.

[22]  M. Salter,et al.  Regulation of kainate receptors by cAMP-dependent protein kinase and phosphatases , 1991, Science.

[23]  L. Squire.  Memory and the hippocampus: a synthesis from findings with rats, monkeys, and humans. , 1992, Psychological review.

[24]  T. Teyler,et al.  N-methyl-d-aspartate receptor-independent long-term potentiation in area CA1 of rat hippocampus: Input-specific induction and preclusion in a non-tetanized pathway , 1992, Neuroscience.