A role for protein kinases and phosphatases in the Ca2+-induced enhancement of hippocampal AMPA receptor-mediated synaptic responses

doi:10.1016/0896-6273(94)90031-0

Neuron

Volume 13, Issue 3, September 1994, Pages 635-643

https://doi.org/10.1016/0896-6273(94)90031-0 Get rights and content

Abstract

We have investigated the effects of inhibitors of protein kinases and protein phosphatases on the NMDA receptor-independent potentiation of evoked and miniature (m) excitatory postsynaptic currents (EPSCs) induced by the entry of Ca²⁺ via voltage-gated Ca²⁺ channels in hippocampal CA1 pyramidal neurons. Voltage pulse-induced potentiation was markedly attenuated when evoked in the presence of the protein kinase blockers KN-62, K-252a, or H-7. Bath application of the protein phosphatase inhibitor calyculin A converted the usual transient potentiation of both evoked and spontaneous EPSCs induced by voltage pulses into a more sustained potentiation. Similarly, the introduction of the phosphatase inhibitors microcystin LIZ or okadaic acid into postsynaptic cells, via patch pipettes, also resulted in a sustained increase in the amplitude of mEPSCs. We propose that entry of Ca²⁺ into CA1 neurons activates calcium/calmodulin-dependent protein kinase II, which leads to an enhanced responsiveness of synaptic AMPA receptor channels. The enhancement is transient, however, owing to postsynaptic phosphatase activity.

References (31)

M.G. Blanton et al.
Whole cell recording from neurons in slices of reptilian and mammalian cerebral cortex
J. Neurosci. Meth.
(1989)
Y. Hashimoto et al.
Potent and preferential inhibition of Ca²⁺/calmodulin-dependent protein kinase II by K252a and its derivative, KT 5926
Biochem. Biophys. Res. Comm.
(1991)
I. Ito et al.
Effects of KN-62, a specific inhibitor of calcium/calmodulin protein kinase II, on long-term potentiation in the rat hippocampus
Neurosci. Lett.
(1991)
D.M. Kullmann et al.
Ca²⁺ entry via postsynaptic voltage-sensitive Ca²⁺ channels can transiently potentiate excitatory synaptic transmission in the hippocampus
Neuron
(1992)
H. Matthies et al.
Differential effects of protein kinase inhibitors on pre-established long-term potentiation in rat hippocampal neurons in vitro
Neurosci. Lett.
(1991)
R.A. Nicoll et al.
A simple chamber for recording from submerged brain slices
J. Neurosci. Meth.
(1981)
H. Tokumitsu et al.
KN-62, 1-[N,O-Bis(5-isoquino-linesulfonyl)-N-methyl-l-tyrosyll-4- phenylpiperizine, a specfic inhibitor of Ca²⁺/calmodulin-dependent protein kinase II
J. Biol. Chem.
(1990)
D.J.A. Wyllie et al.
A rise in postsynaptic Ca²⁺ potentiates miniature excitatory postsynaptic currents and AMPA responses in hippocampal neurons
Neuron
(1994)
T.V.P. Bliss et al.
A synaptic model of memory: long-term potentiation in the hippocampus
Nature
(1993)
P.A. Coleman et al.
Measurement of passive membrane parameters with whole-cell recording from neurons in the intact amphibian retina
J. Neurophysiol.
(1989)

A. Doesmeci et al.

Inhibition of endogenous phosphatase in a postsynaptic fraction allows extensive phosphorylation of the major postsynaptic density protein

J. Neurochem.

(1993)

A. Figurov et al.

Enhancement of AMPA-mediated synaptic transmission by the protein phosphatase inhibitor calyculin A in rat hippocampal slices

Eur. J. Neurosci.

(1993)

P. Forscher et al.

Modulation of calcium channels by norepinephrine in internally dialyzed avian sensory neurons

J. Gen. Physiol.

(1985)

P. Greengard et al.

Enhancement of the glutamate response by cAMP-dependent protein kinase in hippocampal neurons

Science

(1991)

E. Hanse et al.

Staurosporine impairs both short-term and long-term potentiation in the dentate gyrus in vitro

Neuroscience

(1994)

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Neuron

ArticleA role for protein kinases and phosphatases in the Ca2+-induced enhancement of hippocampal AMPA receptor-mediated synaptic responses

Abstract

J. Neurosci. Meth.

Biochem. Biophys. Res. Comm.

Neurosci. Lett.

Neuron

Neurosci. Lett.

J. Neurosci. Meth.

J. Biol. Chem.

Neuron

A synaptic model of memory: long-term potentiation in the hippocampus

Nature

Measurement of passive membrane parameters with whole-cell recording from neurons in the intact amphibian retina

J. Neurophysiol.

Inhibition of endogenous phosphatase in a postsynaptic fraction allows extensive phosphorylation of the major postsynaptic density protein

J. Neurochem.

Enhancement of AMPA-mediated synaptic transmission by the protein phosphatase inhibitor calyculin A in rat hippocampal slices

Eur. J. Neurosci.

Modulation of calcium channels by norepinephrine in internally dialyzed avian sensory neurons

J. Gen. Physiol.

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Science

Staurosporine impairs both short-term and long-term potentiation in the dentate gyrus in vitro

Neuroscience

Article
A role for protein kinases and phosphatases in the Ca²⁺-induced enhancement of hippocampal AMPA receptor-mediated synaptic responses