Abstract
Functional kainate receptors are expressed in the spinal cord substantia gelatinosa region, and their activation contributes to bi-directional regulation of excitatory synaptic transmission at primary afferent synapses with spinal cord substantia gelatinosa neurons. However, no study has reported a role(s) for kainate receptor subtypes in long-term synaptic plasticity phenomena in this region. Using gene-targeted mice lacking glutamate receptor 5 (GLU(K5)) or GLU(K6) subunit, we here show that GLU(K6) subunit, but not GLU(K5) subunit, is involved in the induction of long-term potentiation of excitatory postsynaptic potentials, evoked by two different protocols: (1) high-frequency primary afferent stimulation (100 Hz, 3 s) and (2) low-frequency spike-timing stimulation (1 Hz, 200 pulses). In addition, GLU(K6) subunit plays an important role in the expression of kainate-induced Ca2+ transients in the substantia gelatinosa. On the other hand, genetic deletion of GLU(K5) or GLU(K6) subunit does not prevent the induction of long-term depression. These results indicate that unique expression of kainate receptors subunits is important in regulating spinal synaptic plasticity and thereby processing of sensory information, including pain.
Publication types
-
Comparative Study
-
Research Support, Non-U.S. Gov't
-
Research Support, U.S. Gov't, Non-P.H.S.
MeSH terms
-
6-Cyano-7-nitroquinoxaline-2,3-dione / pharmacology
-
Age Factors
-
Animals
-
Benzoates / pharmacology
-
Cadmium Chloride / pharmacology
-
Calcium / metabolism*
-
Dose-Response Relationship, Radiation
-
Drug Interactions
-
Electric Stimulation / methods
-
Excitatory Amino Acid Agonists / pharmacology
-
Excitatory Amino Acid Antagonists / pharmacology
-
Excitatory Postsynaptic Potentials / drug effects
-
Excitatory Postsynaptic Potentials / genetics
-
Excitatory Postsynaptic Potentials / physiology
-
Excitatory Postsynaptic Potentials / radiation effects
-
Glutamates / pharmacology
-
Glycine / analogs & derivatives
-
Glycine / pharmacology
-
In Vitro Techniques
-
Kainic Acid / pharmacology
-
Membrane Potentials / drug effects
-
Membrane Potentials / genetics
-
Membrane Potentials / physiology
-
Membrane Potentials / radiation effects
-
Mice
-
Mice, Knockout
-
Neuronal Plasticity / drug effects
-
Neuronal Plasticity / genetics
-
Neuronal Plasticity / physiology*
-
Neuronal Plasticity / radiation effects
-
Neurons / drug effects
-
Neurons / metabolism*
-
Patch-Clamp Techniques / methods
-
Protein Subunits / deficiency
-
Receptors, Kainic Acid / deficiency*
-
Substantia Gelatinosa / cytology*
-
alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / pharmacology
Substances
-
Benzoates
-
Excitatory Amino Acid Agonists
-
Excitatory Amino Acid Antagonists
-
Glutamates
-
Protein Subunits
-
Receptors, Kainic Acid
-
4-methylglutamic acid
-
alpha-methyl-4-carboxyphenylglycine
-
6-Cyano-7-nitroquinoxaline-2,3-dione
-
alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid
-
Cadmium Chloride
-
Kainic Acid
-
Calcium
-
Glycine