title: Dexamethasone modulation on cultured human retinal pigment epithelial cell.
abstract: OBJECTIVE
  Dexamethasone(DEX) was tested for its ability to modulate human retinal pigment epithelium(hRPE) cell proliferation in cell culture.
  
  
  METHODS
  DEX in different concentrations was added to cultured hRPE cells. The effects were measured with MTT method, 3H-thymidine(3H-TdR) incorporation and flow cytometry.
  
  
  RESULTS
  DEX increased survival rate and DNA synthesis from 32 mg/L to 320 mg/L under hRPE culture conditions, but paradoxically reduced them at 1,000 mg/L and 3,200 mg/L in dose and time dependent fashion by both MTT assay and 3H-TdR incorporation. The cell numbers in S phase and G2/M phase increased 28.32% at DEX concentration 320 mg/L, in contrast, reduced 41.84% at 1,000 mg/L.
  
  
  CONCLUSIONS
  DEX increased proliferation from 32 mg/L to 320 mg/L, and inhibited proliferation at concentrations greater than 320 mg/L. The inhibiting effect of DEX may happen in s phase and G2/M phase.
authors.affiliation: Department of Ophthalmology, The Air Force General Hospital, Beijing, 100036, China.
authors.forename: B
authors.initials: B
authors.lastname: Liu
authors.forename: Y
authors.initials: Y
authors.lastname: Hui
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: H
authors.initials: H
authors.lastname: Wei
mesh_terms: D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D003907:Dexamethasone / Q000494:pharmacology*; D005434:Flow Cytometry; D006801:Humans; D010857:Pigment Epithelium of Eye / Q000166:cytology*
chemical_list: D000893:Anti-Inflammatory Agents; D003907:Dexamethasone; D004247:DNA