PMID- 23801566
OWN - NLM
STAT- MEDLINE
DCOM- 20140904
LR  - 20211021
IS  - 1532-2149 (Electronic)
IS  - 1090-3801 (Print)
IS  - 1090-3801 (Linking)
VI  - 18
IP  - 2
DP  - 2014 Feb
TI  - Sex differences in mu-opioid receptor expression in trigeminal ganglia under a 
      myositis condition in rats.
PG  - 151-61
LID - 10.1002/j.1532-2149.2013.00352.x [doi]
AB  - BACKGROUND: Peripheral opioid receptor expression is up-regulated under 
      inflammatory conditions, which leads to the increased efficacy of peripherally 
      administered opioids. Sex differences in the effects of inflammation, cytokines 
      and gonadal hormones on mu-opioid receptor (MOR) expression in trigeminal ganglia 
      (TG) are not well understood. METHODS: MOR mRNA and protein levels in TG from 
      male and female Sprague Dawley rats following complete Freund's adjuvant 
      (CFA)-induced muscle inflammation were assessed. Cytokine-induced changes in MOR 
      mRNA expression from TG cultures prepared from intact and gonadectomized male and 
      female, and gonadectomized male rats with testosterone replacement were examined. 
      Behavioural experiments were then performed to examine the efficacy of a 
      peripherally administered MOR agonist in male, female and gonadectomized male 
      rats under a myositis condition. RESULTS: CFA and cytokine treatments induced 
      significant up-regulation of MOR expression in TG from male, but not from female, 
      rats. The cytokine-induced up-regulation of MOR mRNA expression was prevented in 
      TG from orchidectomized (GDX) male rats, which was restored with testosterone 
      replacement. Peripherally administered DAMGO, a specific MOR agonist, 
      significantly attenuated CFA-induced masseter mechanical hypersensitivity only in 
      intact male rats. CONCLUSIONS: Collectively, these data indicate that 
      testosterone plays a key role in the regulation of MOR in TG under inflammatory 
      conditions, and that sex differences in the anti-hyperalgesic effects of 
      peripherally administered opioids are, in part, mediated by peripheral opioid 
      receptor expression levels.
CI  - (c) 2013 European Pain Federation - EFIC(R)
FAU - Zhang, X
AU  - Zhang X
AD  - Department of Anesthesiology, Hospital of Stomatology, The First Affiliated 
      Hospital, China Medical University, Shenyang, China.
FAU - Zhang, Y
AU  - Zhang Y
FAU - Asgar, J
AU  - Asgar J
FAU - Niu, K Y
AU  - Niu KY
FAU - Lee, J
AU  - Lee J
FAU - Lee, K S
AU  - Lee KS
FAU - Schneider, M
AU  - Schneider M
FAU - Ro, J Y
AU  - Ro JY
LA  - eng
GR  - R01 DE019448/DE/NIDCR NIH HHS/United States
GR  - DE019448/DE/NIDCR NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
DEP - 20130625
PL  - England
TA  - Eur J Pain
JT  - European journal of pain (London, England)
JID - 9801774
RN  - 0 (Analgesics, Opioid)
RN  - 0 (Receptors, Opioid, mu)
RN  - 3XMK78S47O (Testosterone)
SB  - IM
MH  - Analgesics, Opioid/metabolism
MH  - Animals
MH  - Female
MH  - Humans
MH  - Inflammation/metabolism
MH  - Male
MH  - Myositis/drug therapy/*metabolism
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Receptors, Opioid, mu/agonists/*metabolism
MH  - Sex Characteristics
MH  - Testosterone/administration & dosage/metabolism/pharmacology
MH  - Trigeminal Ganglion/drug effects/*metabolism
MH  - Up-Regulation
PMC - PMC3916151
MID - NIHMS494095
COIS- Conflict of interest: There is no conflict of interest to declare.
EDAT- 2013/06/27 06:00
MHDA- 2014/09/05 06:00
PMCR- 2015/02/01
CRDT- 2013/06/27 06:00
PHST- 2013/05/31 00:00 [accepted]
PHST- 2013/06/27 06:00 [entrez]
PHST- 2013/06/27 06:00 [pubmed]
PHST- 2014/09/05 06:00 [medline]
PHST- 2015/02/01 00:00 [pmc-release]
AID - 10.1002/j.1532-2149.2013.00352.x [doi]
PST - ppublish
SO  - Eur J Pain. 2014 Feb;18(2):151-61. doi: 10.1002/j.1532-2149.2013.00352.x. Epub 
      2013 Jun 25.