title: [The effect of freezing and low molecular weight heparin treatment on the production of hepatocyte growth factor of human RPE cells].
abstract: OBJECTIVE
  This study is to investigate the human hepatocyte growth factor (HGF) level and proliferation of cultured human retinal pigment epithelial cells (RPE), treated with freezing, or Tedelparin (low molecular weight heparin), or both.
  
  
  METHODS
  Cultured human RPE cells were placed at -80 degrees C freezer for 15 and 60 seconds respectively. One group of freezing-treated cells was kept in culture for another 3 d or 6 d, with or without Tedelparin (25 microl/ml). Another group of freezing-treated cells was injected into the vitreous of rabbits immediately, and 3 d or 6 d later the vitreous of injected rabbits were harvested and put into the medium of cultured human RPE cells, with or without Tedelparin (25 microl/ml). The level of HGF in culture medium and vitreous was measured by ELISA, and the cell proliferation was examined by MTT assay.
  
  
  RESULTS
  The HGF concentration was increased on day 3 in culture medium of freezing-treated human RPE cells (F = 27.36, P < 0.01), and in the rabbit vitreous injected with freezing-treated human RPE cells (F = 6.24, P < 0.01). Tedelparin can reduce the HGF concentration in culture medium of freezing-treated human RPE cells at day 3 and 6 (F = 179.50, P < 0.01). The rabbit vitreous injected with freezing-treated RPE cells can promote the proliferation of normal RPE cells (P < 0.01), which was suppressed by 48 h treatment of Tedelparin (F = 44.90, P < 0.05).
  
  
  CONCLUSIONS
  Freezing may increase the expression of HGF, or promote the proliferation of RPE cells. Tedelparin may suppress the proliferation of RPE cells by inhibiting HGF production.
authors.affiliation: Department of Ophthalmology, The First People's Hospital, Shanghai Jiao Tong University, Shanghai 200080, China. milwang@public7.sta.net.cn
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.forename: Zheng-yu
authors.initials: ZY
authors.lastname: Song
authors.forename: Xiao-feng
authors.initials: XF
authors.lastname: Tao
authors.forename: Qing
authors.initials: Q
authors.lastname: Gu
authors.forename: Xun
authors.initials: X
authors.lastname: Xu
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D017985:Dalteparin / Q000494:pharmacology*; D005260:Female; D005615:Freezing; D017228:Hepatocyte Growth Factor / Q000378:metabolism*; D006801:Humans; D008297:Male; D010857:Pigment Epithelium of Eye / Q000187:drug effects* / Q000378:metabolism; D011817:Rabbits
chemical_list: D017228:Hepatocyte Growth Factor; D017985:Dalteparin