title: [Role of TRPV4 channels in regulation of eNOS expression in brain microvascular endothelial cells under the condition of mechanical stretch].
abstract: OBJECTIVE
  To identify the subtype of transient receptor potential (TRPs) channel involved in stretch-induced injury of human brain microvascular endothelial cells (HBMEC) and to explore the mechanism responsible for eNOS expression.
  
  
  METHODS
  TRPs expression was examined by Western blot and immunocytofluoresence in the cultured HBMEC. Mechanical stretch was performed by mini-type multi-functional bio-impact machine. The levels of free calcium ion in cells were examined by the flow cytometry. The eNOS expression was detected by Western blot.
  
  
  RESULTS
  The mRNA and protein expression of TRPV4 was detected in HBMEC by qRT-PCR, Western blot and immunocytofluoresence. The levels of free calcium ion in the stretch-treated HBMEC was significantly decreased in the presence of TRPV4 specific inhibitor (P<0.001), but there was no difference in calcium levels between the stretch and the control or unspecific inhibitor group (P=0.072 or 0.308). The levels of eNOS protein in the stretch-treated HBMEC were reduced in the presence of TRPV4 specific inhibitor or NOS inhibitor (P<0.05), but it was not changed compared with that in the control group (P>0.05).
  
  
  CONCLUSIONS
  The eNOS expression is up-regulated under the condition of mechanic stretch, which is related to the activation of TRPV4, resulting in the influx of calcium.
authors.affiliation: Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
authors.forename: Jiujun
authors.initials: J
authors.lastname: Pu
authors.affiliation: Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
authors.forename: Ailing
authors.initials: A
authors.lastname: Zhong
authors.affiliation: Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
authors.forename: Lunliang
authors.initials: L
authors.lastname: Ruan
authors.affiliation: Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Jin
authors.affiliation: Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Yang
mesh_terms: D001921:Brain / Q000166:cytology*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000502:physiology*; D006801:Humans; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism*; D013314:Stress, Mechanical; D050916:TRPV Cation Channels / Q000502:physiology*
chemical_list: D050916:TRPV Cation Channels; C416986:TRPV4 protein, human; C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III; D002118:Calcium