1994 Fiscal Year Final Research Report Summary
Study about Regulation of Scleral Growth-using Experimental Myopia-
Grant-in-Aid for General Scientific Research (B)
|Allocation Type||Single-year Grants |
|Research Institution||Tokyo Medical and Dental University |
TOKORO Takashi Tokyo Med & Dent Uni School of Med, Ophthalmology, Professor -> 東京医科歯科大学, 医学部, 教授 (20013865)
KAWSAKI Tsutomu Tokyo Med & Dent Uni School of Med, Ophthalmology, Assistant, 医学部, 助手 (30204712)
AKAZAWA Yoshihiko Tokyo Med & Dent Uni School of Med, Ophthalmology, Assistant, 医学部, 助手 (70159317)
FUNATA Midori Tokyo Med & Dent Uni School of Med, Ophthalmology, Lecturer, 医学部, 講師 (10143554)
|Project Period (FY)
1992 – 1994
|Keywords||Chick / Experimental Myopia / Visual-deprivation / Immunohistochemistry / Tissue culture / Growth factor / Scleral chondrocyte / Scleral fibroblast|
(1) Relationship between method of visual deprivation and induction of myopia : White Leghorn male chicks wearing plastic translucent or black goggles monocularyly showed high myopia with excessive axial elongation under 12hr-light/12hrs-dark cycles. When wearing plastic translucent or black goggles binocularly also showed high myopia with excessive axial elongation under 12hrs-light/12hrs-dark cycles. When wearing translucent or black plastic goggles monocularly did not show any axial elongation under 24hrs-dark condition.
(2) Histological study : In the posterior segment of experimentally myopic sclera, expression of PCNA,TGFbeta、IGF-II,decorin, phosphotyrosine increased by immunohistochemical technique. These results suggest that cell prolioferation and matrix synthesis are increased in the posterior segment of experimentally myopic sclera, which could be regulated by such growth factors as TGFbeta、IGF-II.Electron microscopic observation suggested that active remodelling occurs in th
e myopic cartilaginous sclera and suggested the thinner changes of collagen fibrils in the myopic fibrous sclera.
(3) Biochemical analysis : TGFbeta and bFGF were extracted and were quantitatively analyzed by ELISA.In the posterior segment of experimentally myopic eyes, TGFbeta increased but bFGF was decreased.
(4) Investigation by tissue culture : Cell proliferation of scleral chondrocytes and scleral fibroblasts derived chick embryos was stimulated by such growth factors as TGFbeta , bFGF,TGFalpha、IGF-II,IGF-I and PDGF.Cell proliferation of these scleral cells was also stimulated by co-cultured RPE cells. And this co-culture system revealed that the target of inhibitory effects of apomorphine on scleral growth could be RPE.
(5) Tension experiment with bovine choroid : The degree of stretch was greater in the longitudinal direction than in the circular direction. Thus, it may be possible that the tension becomes one of the factors of axial elongation in the direction of the posterior pole.
(6) Experimental myopia in monkeys : One of the monkeys with high myopia by visual deprivation by lid-suture, showed chorioretinal atrophy in his myopic eyes. Histological observation suggested that aging playd a role in that pathological change. Less
Research Products (11 results)