| Project/Area Number |
04671066
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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 | The University of Tokyo |
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Principal Investigator |
ARAIE Makoto University of Tokyo, School of Medicine, Associate Prof., 医学部(分), 助教授 (00092122)
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| Co-Investigator(Kenkyū-buntansha) |
KOBAYASHI Junko University of Tokyo, School of Medicine, Instructor, 医学部(分), 助手 (30242142)
ISHI Kiyoshi University of Tokyo, School of Medicine, Instructor, 医学部(分), 助手 (50232228)
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| Project Period (FY) |
1992 – 1993
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| Project Status |
Completed (Fiscal Year 1993)
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| Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1993: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1992: ¥1,300,000 (Direct Cost: ¥1,300,000)
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| Keywords | Carboxyfluorescein / Ussing's chamber / Letinal pigment epithelium / Acitive transport / Oxidised glutathione / Blood retinal barrior / Corboxyfluorescein / 酸化型グルタイオン / carboxy fluorescein / 術中潅流液 |
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| Research Abstract |
It is well known that fluid dynamics in the vitreous depends on the function of retinal pigment epithelium (RPE). We already reported characteristics of mode of fluorescein movement across the isolated rabbit RPE-choroid using Ussing's chamber and that this system is suited for studying the functions of RPE, i.e., active transporting function and barrier function against diffusion of exogenous substances. This time, we studied characteristics of mode of carboxyfluorescein movement across the isolated rabbit RPE-choroid. Carboxyfluorescein is known to be a much better tracer dye in studying the barrier function of cell layrs and it is expected that fluid movement across the RPE can be indirectly guessed by calculating the permeability coefficient of RPE to carboxyfluorescein.
Movement of carboxyfluorescein across the isolated RPE-choroid from the choroid to the vitreous side (Inward movement) was found to be by passive diffusion, while its movement from the vitreous to the choroid side (Outward movement) was partly by active transport. At concentration of 30 muM, outward permeability of the isolated rabbit RPE-choroid to carboxyfluorescein was about twice of the inward permeability. Probenecid, ouabain, 2,4-dinitrophenol and hippurate significantly reduced the outward permeability to carboxyfluorescein. A saturation kinetic study revealed that affinity and maximum velocity of reaction of carboxyfluorescein to the carrier is lower than that of fluorescein. The inward permeability to carboxyfluorescein was significantly lower in BSS+GSSG than in BSS or Krebs' Ringer solution, which suggested that GSSG, oxidized glutathione, has beneficial effects on the barrier function of the RPE.
The usage of carboxyfluorescein and Ussing's chamber is suggested to be a useful tool for studying active transport function which is associated with fluid movement across the RPE and barrier function of the RPE.
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