Upregulation of VEGF in murine retina via monocyte recruitment after retinal scatter laser photocoagulation.
OBJECTIVE
This study was conducted to determine changes in the expression of vascular endothelial growth factor (VEGF) in murine retina after retinal scatter laser photocoagulation.


METHODS
Photocoagulation (PHC) was performed on wild-type C57BL/6J mice using a diode laser, and the eyes were enucleated 1, 2, 3, 4, 7, and 14 days after laser treatment. VEGF and monocyte chemoattractant protein (MCP)-1 levels in the sensory retina and retinal pigmented epithelial (RPE) cells in both tissues were measured by ELISA. The VEGF mRNA was measured by real-time RT-PCR. Leukocyte infiltration into the RPE-choroid was determined by flow cytometry. VEGF comparisons between mice subjected to PHC and those treated with monocyte recruitment inhibitor (anti-MCP-1) were performed and statistically analyzed. The expression of VEGF and MCP-1 in the retina was determined by immunohistochemistry.


RESULTS
VEGF protein levels significantly increased 1 day after PHC in both the RPE-choroid and the sensory retina. VEGF concentrations were maximum at day 3 after photocoagulation and stayed elevated until day 7. The number of choroid-infiltrating macrophages was markedly increased in mice with laser treatment compared with those without laser treatment. VEGF expression decreased after treatment with neutralized antibody to monocyte recruitment. We demonstrate that MCP-1 expression in the retina increased markedly after scatter laser photocoagulation by immunohistochemistry and ELISA.


CONCLUSIONS
Retinal scatter laser photocoagulation induced upregulation of VEGF in the sensory retina and RPE-choroid at an early period. The authors speculate that the major source of VEGF in the retina after retinal scatter laser photocoagulation is the recruited monocytes.
Itaya
Masahiro
M
Department of Ophthalmology and Visual Science, Nagoya City University Graduate School of Medical Sciences, Mizuho-ku, Nagoya, Japan. masamedi@sf.starcat.ne.jp
Sakurai
Eiji
E
Nozaki
Miho
M
Yamada
Kiyoshi
K
Yamasaki
Satoshi
S
Asai
Kiyofumi
K
Ogura
Yuichiro
Y
D000818:Animals; D019138:Antibodies, Blocking / Q000494:pharmacology; D002465:Cell Movement; D018932:Chemokine CCL2 / Q000378:metabolism; D002829:Choroid / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D017075:Laser Coagulation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009000:Monocytes / Q000502:physiology*; D010857:Pigment Epithelium of Eye / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012160:Retina / Q000378:metabolism* / Q000601:surgery*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*
D019138:Antibodies, Blocking; C491768:Ccl2 protein, mouse; D018932:Chemokine CCL2; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse