title: [Rapid inhibitory effect of glucocorticoids on peak of [Ca2+]i and PLC in airway smooth muscle].
abstract: OBJECTIVE
  In this study, we pretreated the mice ASMCs by dexamethasone (Dex) within 10 min, to test the peak of [Ca2+]i and phospho-PLCbeta (ser1105) in the cells by treated with Ach.
  
  
  METHODS
  The peak of [Ca2+]i was measured by Fura-2/AM methods and the phospho-PLCbeta-ser1105 was by Western blot, and compared with dexamethasone pretreated groups. Glucocorticoid receptor antagonist RU486 and the protein synthesis inhibitor cycloheximide groups were settled in our study.
  
  
  RESULTS
  Glucocorticoids (GCs) significantly decreased the resting values and peak of [Ca2+]i elevation and elevated the intracellular levels of phospho-PLCbeta (ser1105) in 10 min. Neither the RU486 nor cycloheximide could alter the inhibitory effects of glucocorticoids stated above.
  
  
  CONCLUSIONS
  Our results demonstrate that glucocorticoids exert rapid inhibitory effects. The series of signal changes in this process that restrain the peak of [Ca2+]i may be responsible for the rapid nongenomic inhibitory effects of GCs by reducing the activity of PLC.
authors.affiliation: Center of Nautical and Aviation Medicine PLA, Navy General Hospital, Beijing 100048, China.
authors.forename: Hai-Wen
authors.initials: HW
authors.lastname: Sun
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.forename: Ming-Gao
authors.initials: MG
authors.lastname: Li
authors.forename: Chun-Lei
authors.initials: CL
authors.lastname: Jiang
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology; D005938:Glucocorticoids / Q000494:pharmacology*; D006168:Guinea Pigs; D008297:Male; D015735:Mifepristone / Q000494:pharmacology; D009130:Muscle, Smooth / Q000187:drug effects* / Q000378:metabolism*; D054799:Phospholipase C beta / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014132:Trachea / Q000166:cytology
chemical_list: D005938:Glucocorticoids; D015735:Mifepristone; D003907:Dexamethasone; D054799:Phospholipase C beta; D002118:Calcium