Altered long-term synaptic plasticity and kainate-induced Ca2+ transients in the substantia gelatinosa neurons in GLU(K6)-deficient mice.
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.
Youn
Dong-Ho
DH
Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA.
Voitenko
Nana
N
Gerber
Gabor
G
Park
Yun-Kyung
YK
Galik
Jan
J
Randić
Mirjana
M
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000367:Age Factors; D000818:Animals; D001565:Benzoates / Q000494:pharmacology; D019256:Cadmium Chloride / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D004307:Dose-Response Relationship, Radiation; D004347:Drug Interactions; D004558:Electric Stimulation / Q000379:methods; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D005971:Glutamates / Q000494:pharmacology; D005998:Glycine / Q000031:analogs & derivatives / Q000494:pharmacology; D066298:In Vitro Techniques; D007608:Kainic Acid / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D051379:Mice; D018345:Mice, Knockout; D009473:Neuronal Plasticity / Q000187:drug effects / Q000235:genetics / Q000502:physiology* / Q000528:radiation effects; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D018408:Patch-Clamp Techniques / Q000379:methods; D021122:Protein Subunits / Q000172:deficiency; D018092:Kainic Acid Receptors / Q000172:deficiency*; D013376:Substantia Gelatinosa / Q000166:cytology*; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D001565:Benzoates; D019256:Cadmium Chloride; D002118:Calcium; D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D005971:Glutamates; D005998:Glycine; D007608:Kainic Acid; D021122:Protein Subunits; D018092:Kainic Acid Receptors; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; C046105:4-methylglutamic acid; C079694:alpha-methyl-4-carboxyphenylglycine