TY - JOUR
T1 - Modulation of burst firing of neurons in nucleus reticularis of the thalamus by GluN2C-containing NMDA receptors
AU - Liu, Jinxu
AU - Shelkar, Gajanan P.
AU - Zhao, Fabao
AU - Clausen, Rasmus P.
AU - Dravid, Shashank M.
N1 - Funding Information:
This work was supported by National Science Foundation [Grant 456818], National Institutes of Health National Institute of Neurologic Disorders and Stroke [Grant NS104705] and National Institute of Mental Health [Grant MH116003]. We thank Ratnamala Pavuluri, Pauravi J. Gandhi, and Anna Ayala for excellent technical help. The content is solely the responsibility of the authors. We thank the Wellcome Trust Sanger Institute Mouse Genetics Project (Sanger MGP) and its funders for providing the mutant mouse line Grin2Ctm1 (EGFP/cre/ERT2)Wtsi. Funding and associated primary phenotypic information may be found at www.sanger.ac.uk/mouseportal.
Funding Information:
This work was supported by National Science Foundation [Grant 456818], National Institutes of Health National Institute of Neurologic Disorders and Stroke [Grant NS104705] and National Institute of Mental Health [Grant MH116003]. 1J.L. and G.P.S. contributed equally to this work. https://doi.org/10.1124/mol.119.116780. s This article has supplemental material available at molpharm.aspetjournals.org.
Publisher Copyright:
© 2019 by The American Society for Pharmacology and Experimental Therapeutics.
PY - 2019
Y1 - 2019
N2 - The GluN2C subunit of the NMDA receptor is enriched in the neurons in the nucleus reticularis of the thalamus (nRT), but its role in regulating their function is not well understood. We found that deletion of GluN2C subunit did not affect spike frequency in response to depolarizing current injection or hyperpolarization-induced rebound burst firing of nRT neurons. D-Cycloserine or CIQ (GluN2C/GluN2D positive allosteric modulator) did not affect the depolarization-induced spike frequency in nRT neurons. A newly identified highly potent and efficacious coagonist of GluN1/GluN2C NMDA receptors, AICP ((R)-2-amino-3-(4-(2-ethylphenyl)-1H-indole-2-carboxamido)propanoic acid), was found to reduce the spike frequency and burst firing of nRT neurons in wild type but not GluN2C knockout. This effect was potentially due to facilitation of GluN2C-containing receptors, because inhibition of NMDA receptors by AP5 did not affect spike frequency in nRT neurons. We evaluated the effect of intracerebroventricular injection of AICP. AICP did not affect basal locomotion or prepulse inhibition but facilitated MK-801induced hyperlocomotion. This effect was observed in wildtype but not in GluN2C knockout mice, demonstrating that AICP produces GluN2C-selective effects in vivo. Using a chemogenetic approach, we examined the role of nRT in this behavioral effect. Gq- or Gi-coupled DREADDs were selectively expressed in nRT neurons using Cre-dependent viral vectors and PV-Cre mouse line. We found that similar to AICP effect, activation of Gq- but not Gi-coupled DREADD facilitated MK-801-induced hyperlocomotion. Together, these results identify a unique role of GluN2C-containing receptors in the regulation of nRT neurons and suggest GluN2C-selective in vivo targeting of NMDA receptors by AICP.
AB - The GluN2C subunit of the NMDA receptor is enriched in the neurons in the nucleus reticularis of the thalamus (nRT), but its role in regulating their function is not well understood. We found that deletion of GluN2C subunit did not affect spike frequency in response to depolarizing current injection or hyperpolarization-induced rebound burst firing of nRT neurons. D-Cycloserine or CIQ (GluN2C/GluN2D positive allosteric modulator) did not affect the depolarization-induced spike frequency in nRT neurons. A newly identified highly potent and efficacious coagonist of GluN1/GluN2C NMDA receptors, AICP ((R)-2-amino-3-(4-(2-ethylphenyl)-1H-indole-2-carboxamido)propanoic acid), was found to reduce the spike frequency and burst firing of nRT neurons in wild type but not GluN2C knockout. This effect was potentially due to facilitation of GluN2C-containing receptors, because inhibition of NMDA receptors by AP5 did not affect spike frequency in nRT neurons. We evaluated the effect of intracerebroventricular injection of AICP. AICP did not affect basal locomotion or prepulse inhibition but facilitated MK-801induced hyperlocomotion. This effect was observed in wildtype but not in GluN2C knockout mice, demonstrating that AICP produces GluN2C-selective effects in vivo. Using a chemogenetic approach, we examined the role of nRT in this behavioral effect. Gq- or Gi-coupled DREADDs were selectively expressed in nRT neurons using Cre-dependent viral vectors and PV-Cre mouse line. We found that similar to AICP effect, activation of Gq- but not Gi-coupled DREADD facilitated MK-801-induced hyperlocomotion. Together, these results identify a unique role of GluN2C-containing receptors in the regulation of nRT neurons and suggest GluN2C-selective in vivo targeting of NMDA receptors by AICP.
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U2 - 10.1124/mol.119.116780
DO - 10.1124/mol.119.116780
M3 - Article
C2 - 31160332
AN - SCOPUS:85069557269
VL - 96
SP - 193
EP - 203
JO - Molecular Pharmacology
JF - Molecular Pharmacology
SN - 0026-895X
IS - 2
ER -