title: Interference of Y-27632 on the signal transduction of transforming growth factor beta type 1 in ocular Tenon capsule fibroblasts.
abstract: OBJECTIVE
  To investigate the interfering effect of Y-27632, a ROCK-I selective inhibitor, on the signal transduction pathway of transforming growth factor-β1 (TGF-β1) in ocular Tenon capsule fibroblasts (OTFS) in vitro.
  
  
  METHODS
  After OTFS from passages 4 to 6 in vitro were induced by TGF-β1 and then treated by Y-27632, the changes of the OTFS cell cycles were analyzed via flow cytometry, and the proteins expression of the α-smooth muscular actin (α-SMA), connective tissue growth factor (CTGF), collagen I were calculated by Western blot. After OTFS treated by the different concentrations of Y-27632, the expression levels of the α-SMA, CTGF and collagen I mRNA were assayed by RT-PCR.
  
  
  RESULTS
  Y-27632 had no markedly effect on the OTFS cell cycles. After treated by TGF-β1, OTFS in G1 period significantly increased. The cell cycles distribution by both TGF-β1 and Y-27632 had no remarkable difference from that in control group. Y-27632 significantly inhibited the proteins expressions of both α-SMA and CTGF, while to some extent inhibited that of collagen I. TGF-β1 significantly promoted the proteins expressions of α-SMA, CTGF and collagen I. After OTFS treated by both TGF-β1 and Y-27632, of α-SMA, the protein expression was similar with that in control group (P=0.066>0.05), but the protein expression of CTGF or collagen I, respectively, was significantly different from that in control group (P=0.000<0.01). The differences of expressions of the α-SMA, CTGF and collagen I mRNA in 30, 150, 750µmol/L Y-27632 group were statistically significant, compared with those in control group, respectively (α-SMA, P=0.002, 0.000, 0.000; CTGF, P=0.014, 0.002, 0.001; collagen I, P=0.003, 0.002, 0.000).
  
  
  CONCLUSIONS
  Blocking the Rho/ROCK signaling pathway by using of Y-27632 could inhibit the cellular proliferation and the expression of both CTGF and α-SMA whatever OTFS induced by TGF-β1 or not. Y-27632 suppressed the expression of collagen I mRNA without induction.
authors.affiliation: Department of Ophthalmology, the Second Affiliated Hospital, College of Medicine, Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Zhang
authors.forename: Nai-Xue
authors.initials: NX
authors.lastname: Sun
authors.forename: Zhao-Hui
authors.initials: ZH
authors.lastname: Feng
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jian-Ming
authors.initials: JM
authors.lastname: Wang