1994 Fiscal Year Final Research Report Summary
Basic and Clinical Studies on Choroidal Circulation and its Disorders
Project/Area Number |
04404068
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Research Category |
Grant-in-Aid for General Scientific Research (A)
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Allocation Type | Single-year Grants |
Research Field |
Ophthalmology
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Research Institution | OKAYAMA UNIVERSITY |
Principal Investigator |
MATSUO Nobuhiko Dept. of Ophthalmology, Okayama University Medical School, Professor, 医学部, 教授 (40033047)
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Co-Investigator(Kenkyū-buntansha) |
KAWANISHI Yojiro Dept. of Ophthalm., Okayama Univ. Med. Sch., Assistant, 医学部・附属病院, 助手 (80211184)
SHIRAGA Fumio Dept. of Ophthalm., Okayama Univ. Med. Sch., Assistant Prof., 医学部・附属病院, 講師 (50187530)
OHSHIMA Kohichi Dept. of Ophthalm., Okayama Univ. Med. Sch., Assistant Prof., 医学部・附属病院, 講師 (40176871)
NAKAGAWA Hideki Dept. of Ophthalm., Okayama Univ. Med. Sch., Assistant, 医学部・附属病院, 助手 (10252967)
MATSUO Toshihiko Dept. of Ophthalm., Okayama Univ. Med. Sch., Assistant, 医学部・附属病院, 助手 (90211565)
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Project Period (FY) |
1992 – 1994
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Keywords | Choroid / Circulatory regulation / Nerve factor / Endothelial factor / Autoregulation / Scanning laser ophthalmoscope / Indocyanine green / Age - related macular degeneration |
Research Abstract |
1. Studies on nerve factors and endothelial factors which regulate choroidal circulation. (1) Nerve factors - Both nor - adrenergic and acetylcholin - esterage positive nerve fibers were distributed around smooth muscle cells of choroidal arterioles of rabbits. Adrenergic nerve endings were also recognized close to choroidal melanocytes of monkeys. Choroidal blood flow increased significantly after cutting the cervical sympathetic nerve in rabbits, and decreased after stimulating it. (2) Prostaglandins - Choroidal blood flow of rabbits increased significantly after administrating a small dose of prostaglandin IィイD22ィエD2 - derivative and EィイD21ィエD2. (3) It was suggested that the renin - angiotensin system was involved in choroidal circulation. (4) Choroidal blood flow of rabbits decreased significantly after intravenous or intravitreal injection of endothelin (ET) - 1. An endothelin A - receptor anatagonist improved choroidal circulatory disorders of rats when ET - 1 participated in the
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disorder. (5) Choroidal blood flow of rabbits decreased significantly after intravenous administration of specific inhibitor of an endothelium - derived relaxing factor. (6) Choroidal blood flow decreased significantly in rabbits with selective damage of the retinal layer. The structure of choriocapillaris was thought to be regulated by the retinal pigment epithelium. From above results, choroidal circulation was regulated by both nerve and endothelial factors, and also by choroidal melanocytes and the retinal outer layer. There also seemed to be a possibility of autoregulation of choroidal circulation. 2. Basic and clinical studies on indocyanine green video angiography using the scanning laser ophthalmoloscope. (1) The diameters of choroidal vessels were measured digitally by using the scanning laser ophthalmoscope and image analysis system. This digital technique was useful for measuring how the diameters of choroidal vessels of experimental animals were changed especially after medical treatment. (2) This technique was also useful for the clinical detection of the choroidal circulatory disorder in various fundus diseases, especially the early detection of feeder vessels into subfoveal choroidal neovascularization of age - related macular degeneration. And selective localized laser photocoagulation for the feeder vessels were effective to age - related macular degeneration. Less
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