Gabaergic influence on temporomandibular joint-responsive spinomedullary neurons depends on estrogen status

A. Tashiro; David A Bereiter; R. Thompson; Y. Nishida

doi:10.1016/j.neuroscience.2013.11.053

Gabaergic influence on temporomandibular joint-responsive spinomedullary neurons depends on estrogen status

A. Tashiro, David A Bereiter, R. Thompson, Y. Nishida

Basic Sciences

Research output: Contribution to journal › Article › peer-review

15 Scopus citations

Abstract

Sensory input from the temporomandibular joint (TMJ) to neurons in superficial laminae at the spinomedullary (Vc/C_1-2) region is strongly influenced by estrogen status. This study determined if GABAergic mechanisms play a role in estrogen modulation of TMJ nociceptive processing in ovariectomized female rats treated with high- (HE) or low-dose (LE) estradiol (E2) for 2days. Superficial laminae neurons were activated by ATP (1mM) injections into the joint space. The selective GABA_A receptor antagonist, bicuculline methiodide (BMI, 5 or 50μM, 30μl), applied at the site of recording greatly enhanced the magnitude and duration of ATP-evoked responses in LE rats, but not in units from HE rats. The convergent cutaneous receptive field (RF) area of TMJ neurons was enlarged after BMI in LE but not HE rats, while resting discharge rates were increased after BMI independent of estrogen status. By contrast, the selective GABA_A receptor agonist, muscimol (50μM, 30μl), significantly reduced the magnitude and duration of ATP-evoked activity, resting discharge rate, and cutaneous RF area of TMJ neurons in LE and HE rats, whereas lower doses (5μM) affected only units from LE rats. Protein levels of GABA_A receptor β3 isoform at the Vc/C_1-2 region were similar for HE and LE rats. These results suggest that GABAergic mechanisms contribute significantly to background discharge rates and TMJ-evoked input to superficial laminae neurons at the Vc/C_1-2 region. Estrogen status may gate the magnitude of GABAergic influence on TMJ neurons at the earliest stages of nociceptive processing at the spinomedullary region.

Original language	English (US)
Pages (from-to)	53-62
Number of pages	10
Journal	Neuroscience
Volume	259
DOIs	https://doi.org/10.1016/j.neuroscience.2013.11.053
State	Published - Feb 4 2014

Bibliographical note

Funding Information:
The authors have no financial or other relationships to report that might lead to a conflict of interest. This work was supported by JSPS KAKENHI (Grant Number 25462908), Promotion Research from National Defense Medical College (H24) and a grant from the US National Institutes of Health (DE-12758) to D.A.B.

Keywords

GABAA receptor
Nociception
Sex steroids
Trigeminal brainstem

Access

10.1016/j.neuroscience.2013.11.053

OpenUrl availability

Full text

Cite this

@article{414639c6b99c4f81b88a5198261164fe,

title = "Gabaergic influence on temporomandibular joint-responsive spinomedullary neurons depends on estrogen status",

abstract = "Sensory input from the temporomandibular joint (TMJ) to neurons in superficial laminae at the spinomedullary (Vc/C1-2) region is strongly influenced by estrogen status. This study determined if GABAergic mechanisms play a role in estrogen modulation of TMJ nociceptive processing in ovariectomized female rats treated with high- (HE) or low-dose (LE) estradiol (E2) for 2days. Superficial laminae neurons were activated by ATP (1mM) injections into the joint space. The selective GABAA receptor antagonist, bicuculline methiodide (BMI, 5 or 50μM, 30μl), applied at the site of recording greatly enhanced the magnitude and duration of ATP-evoked responses in LE rats, but not in units from HE rats. The convergent cutaneous receptive field (RF) area of TMJ neurons was enlarged after BMI in LE but not HE rats, while resting discharge rates were increased after BMI independent of estrogen status. By contrast, the selective GABAA receptor agonist, muscimol (50μM, 30μl), significantly reduced the magnitude and duration of ATP-evoked activity, resting discharge rate, and cutaneous RF area of TMJ neurons in LE and HE rats, whereas lower doses (5μM) affected only units from LE rats. Protein levels of GABAA receptor β3 isoform at the Vc/C1-2 region were similar for HE and LE rats. These results suggest that GABAergic mechanisms contribute significantly to background discharge rates and TMJ-evoked input to superficial laminae neurons at the Vc/C1-2 region. Estrogen status may gate the magnitude of GABAergic influence on TMJ neurons at the earliest stages of nociceptive processing at the spinomedullary region.",

keywords = "GABAA receptor, Nociception, Sex steroids, Trigeminal brainstem",

author = "A. Tashiro and Bereiter, {David A} and R. Thompson and Y. Nishida",

note = "Funding Information: The authors have no financial or other relationships to report that might lead to a conflict of interest. This work was supported by JSPS KAKENHI (Grant Number 25462908), Promotion Research from National Defense Medical College (H24) and a grant from the US National Institutes of Health (DE-12758) to D.A.B.",

year = "2014",

month = feb,

day = "4",

doi = "10.1016/j.neuroscience.2013.11.053",

language = "English (US)",

volume = "259",

pages = "53--62",

journal = "Neuroscience",

issn = "0306-4522",

publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Gabaergic influence on temporomandibular joint-responsive spinomedullary neurons depends on estrogen status

AU - Tashiro, A.

AU - Bereiter, David A

AU - Thompson, R.

AU - Nishida, Y.

N1 - Funding Information: The authors have no financial or other relationships to report that might lead to a conflict of interest. This work was supported by JSPS KAKENHI (Grant Number 25462908), Promotion Research from National Defense Medical College (H24) and a grant from the US National Institutes of Health (DE-12758) to D.A.B.

PY - 2014/2/4

Y1 - 2014/2/4

N2 - Sensory input from the temporomandibular joint (TMJ) to neurons in superficial laminae at the spinomedullary (Vc/C1-2) region is strongly influenced by estrogen status. This study determined if GABAergic mechanisms play a role in estrogen modulation of TMJ nociceptive processing in ovariectomized female rats treated with high- (HE) or low-dose (LE) estradiol (E2) for 2days. Superficial laminae neurons were activated by ATP (1mM) injections into the joint space. The selective GABAA receptor antagonist, bicuculline methiodide (BMI, 5 or 50μM, 30μl), applied at the site of recording greatly enhanced the magnitude and duration of ATP-evoked responses in LE rats, but not in units from HE rats. The convergent cutaneous receptive field (RF) area of TMJ neurons was enlarged after BMI in LE but not HE rats, while resting discharge rates were increased after BMI independent of estrogen status. By contrast, the selective GABAA receptor agonist, muscimol (50μM, 30μl), significantly reduced the magnitude and duration of ATP-evoked activity, resting discharge rate, and cutaneous RF area of TMJ neurons in LE and HE rats, whereas lower doses (5μM) affected only units from LE rats. Protein levels of GABAA receptor β3 isoform at the Vc/C1-2 region were similar for HE and LE rats. These results suggest that GABAergic mechanisms contribute significantly to background discharge rates and TMJ-evoked input to superficial laminae neurons at the Vc/C1-2 region. Estrogen status may gate the magnitude of GABAergic influence on TMJ neurons at the earliest stages of nociceptive processing at the spinomedullary region.

AB - Sensory input from the temporomandibular joint (TMJ) to neurons in superficial laminae at the spinomedullary (Vc/C1-2) region is strongly influenced by estrogen status. This study determined if GABAergic mechanisms play a role in estrogen modulation of TMJ nociceptive processing in ovariectomized female rats treated with high- (HE) or low-dose (LE) estradiol (E2) for 2days. Superficial laminae neurons were activated by ATP (1mM) injections into the joint space. The selective GABAA receptor antagonist, bicuculline methiodide (BMI, 5 or 50μM, 30μl), applied at the site of recording greatly enhanced the magnitude and duration of ATP-evoked responses in LE rats, but not in units from HE rats. The convergent cutaneous receptive field (RF) area of TMJ neurons was enlarged after BMI in LE but not HE rats, while resting discharge rates were increased after BMI independent of estrogen status. By contrast, the selective GABAA receptor agonist, muscimol (50μM, 30μl), significantly reduced the magnitude and duration of ATP-evoked activity, resting discharge rate, and cutaneous RF area of TMJ neurons in LE and HE rats, whereas lower doses (5μM) affected only units from LE rats. Protein levels of GABAA receptor β3 isoform at the Vc/C1-2 region were similar for HE and LE rats. These results suggest that GABAergic mechanisms contribute significantly to background discharge rates and TMJ-evoked input to superficial laminae neurons at the Vc/C1-2 region. Estrogen status may gate the magnitude of GABAergic influence on TMJ neurons at the earliest stages of nociceptive processing at the spinomedullary region.

KW - GABAA receptor

KW - Nociception

KW - Sex steroids

KW - Trigeminal brainstem

UR - http://www.scopus.com/inward/record.url?scp=84891139537&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84891139537&partnerID=8YFLogxK

U2 - 10.1016/j.neuroscience.2013.11.053

DO - 10.1016/j.neuroscience.2013.11.053

M3 - Article

C2 - 24316475

AN - SCOPUS:84891139537

SN - 0306-4522

VL - 259

SP - 53

EP - 62

JO - Neuroscience

JF - Neuroscience

ER -

Gabaergic influence on temporomandibular joint-responsive spinomedullary neurons depends on estrogen status

Abstract

Bibliographical note

Keywords

Access

OpenUrl availability

Other files and links

Fingerprint

Cite this