AQUEOUS HUMOUR AND ULTRAVIOLET RADIATION

@article{Ringvold1980AQUEOUSHA,
  title={AQUEOUS HUMOUR AND ULTRAVIOLET RADIATION},
  author={Amund Ringvold},
  journal={Acta Ophthalmologica},
  year={1980},
  volume={58}
}
  • A. Ringvold
  • Published 1 February 1980
  • Medicine
  • Acta Ophthalmologica
Studies on the ultraviolet ray absorption in the aqueous humour of rabbit, cat, monkey, guinea pig, and rat showed marked species differences. In the rabbit aqueous the ascorbic acid, the proteins, and some amino acids (tyrosine, phenylalanine, cystine, and tryptophane) are together responsible for the total absorption, and a very great part of it refers to the ascorbic acid content. Accordingly, species with significant amounts of ascorbic acid in the aqueous (monkey, rabbit, guinea pig) have… Expand
UV-Absorbing Compounds in the Aqueous Humor from Aquatic Mammals and Various Non-Mammalian Vertebrates
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TLDR
Uric acid is a significant UV-absorbing substance in the aqueous humor of diurnal birds with its peak absorbance at 292 nm, and the hypothesis that the aQueous humor acts as a UV filter seems to be valid also for the avian eye. Expand
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TLDR
The results were consistent with the hypothesis that high ascorbic acid in diurnal animals protects the lens against the cataractogenic effect of UV radiation in sunlight and had a protective effect against UV-induced DNA damage to lens epithelium. Expand
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  • Chemistry, Medicine
  • Investigative ophthalmology & visual science
  • 1989
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In vivo aqueous, vitreous and CSF transport results from the guinea pig indicate active transport mechanisms for ascorbic acid that prefer the ascorBate over the dehydroascorbate moiety and are probably different from the carrier-facilitated diffusion mechanisms for D-glucose, which do not move molecules against a concentration gradient. Expand
A Comparative Study of Ascorbic Acid Entry into Aqueous and Vitreous Humors of the Rat and Guinea Pig
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Ascorbic acid levels in the aqueous humor of nocturnal and diurnal mammals.
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A wide range of ascorbic acid levels in the aqueous humor was found, and most of the animals considered to be diurnal had higher ascor bicarbonate levels than the nocturnal animals, suggesting that ascorBic acid may play a protective role in those animals who are most exposed to light. Expand
Alterations in Ascorbic Acid Transport Into the Lens of Streptozotocin-lnduced Diabetic Rats and Guinea Pigs
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Ascorbic Acid as a Free Radical Scavenger in Porcine and Bovine Aqueous Humour
TLDR
The experiments suggest that AA is the major contributor to the antioxidant activity of porcine and bovine AH and the role of AA to serve as an antioxidant in AH. Expand
Quenching of UV-induced fluorescence by ascorbic acid in the aqueous humour.
  • A. Ringvold
  • Medicine
  • Acta ophthalmologica Scandinavica
  • 1995
TLDR
The marked fluorescence of tryptophane and protein was considerably quenched by the ascorbic acid, an observation not shown before, indicating that the aqueous humour minimizes UV-radiation to the lens in diurnal animals through three different mechanisms: 1) Absorption, 2) Fluorescence-quenching, and 3) fluorescence-mediated ray transformation. Expand
Is the high concentration of ascorbic acid in the eye an adaptation to intense solar irradiation?
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It is discovered that of two closely related species of spiny mice, the diurnal species (Acomys russatus) has a concentration in aqueous humor that is 35 times higher than that of the nocturnal species of Acomys cahirinus. Expand
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TLDR
In a model experiment based on conditions in the rabbit cornea epithelium, it is shown that the ascorbic acid in these cells is roughly responsible for ultraviolet ray absorption of the same order as proteins and nucleic acids in the 250–290 nm spectral range. Expand
Ascorbic acid in aqueous humor and serum of patients with and without cataract; physiologic significance of relative concentrations.
TLDR
The chief evidence in support of the theories that associate the lens with the maintenance of relatively high concentrations of ascorbic acid in the aqueous humor is the observation that the concentration of the acid is less than normal when the lens is cataractous or absent. Expand
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Experiments on the dynamic aspects of the transfer from blood to aqueous humour of ascorbic acid and of its reversibly oxidized form, dehydro-ascorbic acid will be described. Expand
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In the aqueous humour and the corneal epithelium of rabbits, the ascorbic acid levels were investigated using the photometric assay with 2,6-dichlorophenolindophenol. After injection of 300 mg/kgExpand
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TLDR
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TLDR
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The eye of the bush baby has been studied, since in size it lies between those of the rabbit and guinea-pig, and the lens occupies a large percentage of the ocular contents, so the relatively low bicarbonate concentration was compensated by a more rapid turnover of the fluid. Expand
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TLDR
The results support the idea that age-related cataractous changes in the lens are accelerated by near UV light. Expand
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