PMID- 21296645
OWN - NLM
STAT- MEDLINE
DCOM- 20110804
LR  - 20211020
IS  - 1873-7544 (Electronic)
IS  - 0306-4522 (Print)
IS  - 0306-4522 (Linking)
VI  - 180
DP  - 2011 Apr 28
TI  - Sex differences in the contribution of ATP-sensitive K+ channels in trigeminal 
      ganglia under an acute muscle pain condition.
PG  - 344-52
LID - 10.1016/j.neuroscience.2011.01.045 [doi]
AB  - In this study, we examined whether functional subunits of the ATP-dependent K+ 
      channel (KATP) are expressed in trigeminal ganglia (TG), which contains sensory 
      neurons that innervate oral and facial structures. We also investigated whether 
      direct activation of the KATP effectively attenuates mechanical hypersensitivity 
      in the context of an acute orofacial muscle pain condition. The KATP expression 
      in TG and behavioral studies were conducted in age matched male and female 
      Sprague-Dawley rats. RT-PCR experiments showed that the mRNAs for the inwardly 
      rectifying pore-forming subunits, Kir6.1 and Kir6.2, as well as the regulatory 
      sulfonylurea subunits, SUR1 and SUR2, were reliably detected in TG. Subsequent 
      western blot analysis confirmed that proteins for all four subunits are expressed 
      in TG, and showed that Kir6.2 is expressed at a significantly higher level in 
      male TG compared to that of female rats. This observation was confirmed by the 
      immunohistochemical demonstration of higher percentages of Kir6 positive masseter 
      afferents in female rats. Masseteric injection of capsaicin evokes a time 
      dependent increase in masseter sensitivity to noxious mechanical stimulation. A 
      specific KATP agonist, pinacidil, dose-dependently attenuated the 
      capsaicin-induced mechanical hypersensitivity in male rats. The dose of pinacidil 
      (20 mug) that completely blocked the capsaicin responses in male rats was 
      ineffective in female rats regardless of their estrus phases. Only at the highest 
      dose (300 mug) we used, pinacidil was partially effective in female rats. 
      Similarly, another KATP agonist, diazoxide which targets different KATP subunits 
      also showed sex specific responses in attenuating capsaicin-induced masseter 
      hypersensitivity. These data suggested that sex differences in functional KATP 
      expression in TG may underlie sex specific responses to KATP agonists. The 
      present study provided novel information on sex differences in KATP expression in 
      TG and its contribution under an orofacial muscle pain condition.
CI  - Copyright (c) 2011 IBRO. Published by Elsevier Ltd. All rights reserved.
FAU - Niu, K
AU  - Niu K
AD  - Program in Neuroscience, Department of Neural and Pain Sciences, University of 
      Maryland Baltimore School of Dentistry, 650 West Baltimore Street, Baltimore, MD 
      21201, USA.
FAU - Saloman, J L
AU  - Saloman JL
FAU - Zhang, Y
AU  - Zhang Y
FAU - Ro, J Y
AU  - Ro JY
LA  - eng
GR  - R01 DE019448/DE/NIDCR NIH HHS/United States
GR  - R01 DE019448-03/DE/NIDCR NIH HHS/United States
GR  - R01 DE19448/DE/NIDCR NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
DEP - 20110202
PL  - United States
TA  - Neuroscience
JT  - Neuroscience
JID - 7605074
RN  - 0 (KATP Channels)
SB  - IM
MH  - Animals
MH  - Area Under Curve
MH  - Blotting, Western
MH  - Female
MH  - Hyperalgesia/metabolism/physiopathology
MH  - Immunohistochemistry
MH  - KATP Channels/*metabolism
MH  - Male
MH  - Masseter Muscle/*innervation
MH  - Pain/*metabolism/physiopathology
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Reverse Transcriptase Polymerase Chain Reaction
MH  - *Sex Characteristics
MH  - Trigeminal Ganglion/*metabolism
PMC - PMC3124308
MID - NIHMS271298
COIS- Conflicts of interest: There are no conflicts of interest associated with the 
      present study.
EDAT- 2011/02/08 06:00
MHDA- 2011/08/05 06:00
PMCR- 2012/04/28
CRDT- 2011/02/08 06:00
PHST- 2010/11/12 00:00 [received]
PHST- 2011/01/20 00:00 [revised]
PHST- 2011/01/20 00:00 [accepted]
PHST- 2011/02/08 06:00 [entrez]
PHST- 2011/02/08 06:00 [pubmed]
PHST- 2011/08/05 06:00 [medline]
PHST- 2012/04/28 00:00 [pmc-release]
AID - S0306-4522(11)00097-2 [pii]
AID - 10.1016/j.neuroscience.2011.01.045 [doi]
PST - ppublish
SO  - Neuroscience. 2011 Apr 28;180:344-52. doi: 10.1016/j.neuroscience.2011.01.045. 
      Epub 2011 Feb 2.