Beta-adrenergic receptor activation during distinct patterns of stimulation critically modulates the PKA-dependence of LTP in the mouse hippocampus

Learn Mem. 2008 Apr 25;15(5):281-9. doi: 10.1101/lm.829208. Print 2008 May.

Abstract

Activation of beta-adrenergic receptors (beta-ARs) enhances hippocampal memory consolidation and long-term potentiation (LTP), a likely mechanism for memory storage. One signaling pathway linked to beta-AR activation is the cAMP-PKA pathway. PKA is critical for the consolidation of hippocampal long-term memory and for the expression of some forms of long-lasting hippocampal LTP. How does beta-AR activation affect the PKA-dependence, and persistence, of LTP elicited by distinct stimulation frequencies? Here, we use in vitro electrophysiology to show that patterns of stimulation determine the temporal phase of LTP affected by beta-AR activation. In addition, only specific patterns of stimulation recruit PKA-dependent LTP following beta-AR activation. Impairments of PKA-dependent LTP maintenance generated by pharmacologic or genetic deficiency of PKA activity are also abolished by concurrent activation of beta-ARs. Taken together, our data show that, depending on patterns of synaptic stimulation, activation of beta-ARs can gate the PKA-dependence and persistence of synaptic plasticity. We suggest that this may allow neuromodulatory receptors to fine-tune neural information processing to meet the demands imposed by numerous synaptic activity profiles. This is a form of "metaplasticity" that could control the efficacy of consolidation of hippocampal long-term memories.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic beta-Agonists / administration & dosage
  • Adrenergic beta-Agonists / pharmacology
  • Animals
  • Carbazoles / administration & dosage
  • Carbazoles / pharmacology
  • Cyclic AMP-Dependent Protein Kinases / antagonists & inhibitors
  • Electric Stimulation
  • Enzyme Inhibitors / administration & dosage
  • Enzyme Inhibitors / pharmacology
  • Female
  • Hippocampus / drug effects*
  • Hippocampus / metabolism
  • Intracellular Signaling Peptides and Proteins / administration & dosage
  • Intracellular Signaling Peptides and Proteins / pharmacology*
  • Isoproterenol / administration & dosage
  • Isoproterenol / pharmacology
  • Locus Coeruleus / drug effects
  • Long-Term Potentiation / drug effects*
  • Memory / drug effects
  • Mice
  • Mice, Inbred C57BL
  • Mice, Mutant Strains
  • Mice, Transgenic
  • Nerve Net / drug effects
  • Neuronal Plasticity / drug effects
  • Pyrroles / administration & dosage
  • Pyrroles / pharmacology
  • RGS Proteins / drug effects
  • Receptors, Adrenergic, beta / drug effects*
  • Receptors, Adrenergic, beta / metabolism
  • Synaptic Transmission / drug effects

Substances

  • Adrenergic beta-Agonists
  • Carbazoles
  • Enzyme Inhibitors
  • Intracellular Signaling Peptides and Proteins
  • Pyrroles
  • RGS Proteins
  • Receptors, Adrenergic, beta
  • protein kinase modulator
  • KT 5720
  • Cyclic AMP-Dependent Protein Kinases
  • Isoproterenol