title: Relationship of glucocorticoid receptor expression in peripheral blood mononuclear cells and the cochlea of guinea pigs and effects of dexamethasone administration.
abstract: BACKGROUND
  Glucocorticoids (GCs) are widely used to treat sudden sensorineural hearing loss (SSNHL) and significantly improve hearing. However, GC insensitivity has been observed in some patients of SSNHL.
  
  
  OBJECTIVE
  To study the correlation between GR expression in peripheral blood mononuclear cells (PBMCs) and in the cochlea of guinea pigs at mRNA and protein levels.
  
  
  METHODS
  One group of guinea pigs received dexamethasone (10 mg/kg/day) intraperitoneally for 7 consecutive days (dexamethasone group), and another group of guinea pigs received normal saline (control group). Real time PCR and Western blotting were used to detect the expression of GR mRNA and GR protein in PBMCs and the cochleae.
  
  
  RESULTS
  The GR mRNA and GR protein were detected in both PBMCs and the cochlear tissue of guinea pigs. GR mRNA and GR protein levels in PBMCs were positively correlated with those in the cochlea. The expression of GR mRNA and GR protein was significantly increased in the dexamethasone group compared to the control group.
  
  
  CONCLUSIONS
  Levels of GR mRNA and GR protein in the PBMCs were positively correlated with those in the cochlea of guinea pigs. Systemic dexamethasone treatment can significantly up-regulate GR expression in PBMCs and in the cochlea. Measurement of the GR level in PBMCs could be used as an indicator of GR level in the cochlea.
authors: Department of Otolaryngology-Head and Neck Surgery, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, China.
authors: Ling
authors: L
authors: Lu
authors: Yanhong
authors: Y
authors: Dai
authors: Xiaoping
authors: X
authors: Du
authors: Wandong
authors: W
authors: She
authors: Xiuling
authors: X
authors: Zhang
authors: Qin
authors: Q
authors: Wu
authors: Wenjie
authors: W
authors: Yuan
authors: Feng
authors: F
authors: Chen
mesh_terms: D000818:Animals; D003051:Cochlea / Q000187:drug effects / Q000378:metabolism*; D003907:Dexamethasone / Q000008:administration & dosage* / Q000494:pharmacology*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D006168:Guinea Pigs; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011965:Receptors, Glucocorticoid / Q000235:genetics* / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D011965:Receptors, Glucocorticoid; D003907:Dexamethasone