title: Short pulse laser induces less inflammatory cytokines in the murine retina after laser photocoagulation.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effect of pulse duration on the expression of inflammatory cytokines in the murine retina after laser photocoagulation treatment with a PASCAL(®) pattern scan laser photocoagulator and conventional laser treatment.
  
  
  METHODS
  Retinal scatter laser photocoagulation was performed on C57BL/6J mice using a short pulse (10 ms) with a PASCAL laser or conventional settings (100 ms) with a multicolor laser. Eyes were enucleated before treatment (control) and 1 day, 3 days and 7 days after treatment. The levels of inflammatory cytokines (i.e., VEGF, MCP-1, RANTES and IL-6) in the retina/choroid were quantified by an ELISA. The expression patterns of VEGF and macrophages (i.e., F4/80) in the retina/choroid were evaluated by immunohistochemistry.
  
  
  RESULTS
  The levels of RANTES, IL-6 and MCP-1 after PASCAL and conventional laser treatments were significantly elevated compared with controls (p < 0.05). Conventional laser treatment, but not PASCAL treatment, resulted in the up-regulation of VEGF. RANTES and IL-6 levels on day 1 and MCP-1 levels on day 3 in the sensory retina were also significantly up-regulated with conventional laser treatment compared with PASCAL treatment (p < 0.05). Immunohistochemical analysis showed that PASCAL treatment was associated with lower VEGF and F4/80 expression levels compared with conventional laser treatment.
  
  
  CONCLUSIONS
  Our data suggested that the short pulse duration induced fewer inflammatory cytokines in the sensory retina compared with the conventional pulse duration. Short pulse laser photocoagulation with the PASCAL may prevent macular edema after panretinal photocoagulation.
authors.affiliation: Department of Ophthalmology and Visual Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Aiko
authors.initials: A
authors.lastname: Ito
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Hirano
authors.forename: Miho
authors.initials: M
authors.lastname: Nozaki
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ashikari
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sugitani
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Ogura
mesh_terms: D000818:Animals; D000943:Antigens, Differentiation / Q000378:metabolism; D018932:Chemokine CCL2 / Q000378:metabolism*; D018946:Chemokine CCL5 / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D019084:Fluorescent Antibody Technique, Indirect; D015850:Interleukin-6 / Q000378:metabolism*; D017075:Laser Coagulation / Q000295:instrumentation / Q000379:methods*; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012160:Retina / Q000378:metabolism / Q000601:surgery*; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D000943:Antigens, Differentiation; C491768:Ccl2 protein, mouse; C503460:Ccl5 protein, mouse; D018932:Chemokine CCL2; D018946:Chemokine CCL5; D015850:Interleukin-6; D042461:Vascular Endothelial Growth Factor A; C036763:monocyte-macrophage differentiation antigen; C467480:vascular endothelial growth factor A, mouse