| Project/Area Number |
05671460
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Ophthalmology
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| Research Institution | Hamamatsu University School of Medicine |
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Principal Investigator |
HIRAMITSU Tadahisa HAMAMATSU UNIV.SCHOOL OF MEDICINE PHOTON MEDICAL RESEARCH CENTER., PROFESSOR, 光量子医学研究センター, 教授 (00084567)
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| Co-Investigator(Kenkyū-buntansha) |
MIURA Yoshihisa HAMAMATSU UNIV.SCHOOL OF MEDICINE DEPARTMENT OF OPHTHALMOLOGY., INSTRUCTOR, 医学部, 助手 (10165970)
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| Project Period (FY) |
1993 – 1994
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| Project Status |
Completed (Fiscal Year 1994)
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| Budget Amount *help |
¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1994: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1993: ¥800,000 (Direct Cost: ¥800,000)
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| Keywords | ULTRA-VIOLET / CATARACT / ASCORBIC ACID / SUN LIGHT / ACTIVE OXYGEN / 血液房水柵 |
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| Research Abstract |
In order to study on the role of active oxygen in the mechanism of ultraviolet (UV) induced cataract, the effects of UV on the aqueous humor were examined.
1.The effects of UV on ascorbic acid (AsA) in the aqueus humor.
1) After the irradiation of UV-C,UV-B and UV-A for 30 min on the aqueous humor in vitro, AsA which was measured by HPLC decreased significantly in the two former and the decrease was greater in the aqueous irradiated with UV-C than in that with UV-B.
2) AsA in the aqueous of the eye which received UV-B or UV-A irradiation for 10 min decreased 1 days after the irradiation, and the decrease bacame greater 2 weeks later, much more in the aqueous irradiated with UV-B than in that with UV-A.The irradiation of UV-A as well as UV-B to the anterior segments of the eye cause the decrease of AsA in the aqueous humor which may be due to the damage of active transport system of AsA through the blood aqueous barrier, resulting in the dysfunction of the defensive system against the oxidative stress.
2.The effects of sun light on the blood aqueous barrier.
After exposure of the eyes to sun light outdoors for several minutes, the protein amount of the aqueous humor of the eye which was measured with laser flare cell meter increased significantly. It means that the disruption of the blood aqueous barrier was easily induced by the exposure to sun light.
These results revealed that UV-A as well as UV-B and sun light cause the changes of the biochemical composions in the aqueous humor which may be followed by the cataracgenic conditions.
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