Documenta Ophthalmologica

, Volume 26, Issue 1, pp 164–170 | Cite as

Transfer of D-isoascorbic acid and L-ascorbic acid into guinea pig eyes

  • Erik Linnér
  • Karin Nordström
Article

Summary

A comparison was made between the transfer of D-isoascorbic acid and L-ascorbic acid into the guinea pig eye. Saturation phenomena are demonstrated. A much higher plasma level is required for D-isoascorbic acid than for ascorbic acid in order to reach the saturation level in the aqueous humour. The affinity of ascorbic acid to the transport substrate is estimated to be 4–5 times higher than that of D-isoascorbic acid. The results are in agreement with the assumption that the transport mechanism is the same for the two substances.

Keywords

Ascorbic Acid Anterior Chamber Aqueous Humour Transport Substrate Posterior Chamber 

Résumé

On a comparé chez le cobaye la pénétration dans l'oeil de l'acide D-isoascorbique à celle de l'acide L-ascorbique. Des phénomènes de saturation ont été démontrés. Pour obtenir la saturation dans l'humeur aqueuse, il faut atteindre des taux bien plus élevés dans le plasma avec l'acide D-isoascorbique qu'avec l'acide ascorbique. L'affinité de ce dernier au substrat de transport est estimée être 4–5 supérieure à celle de l'acide D-isoascorbique. Les résultats confirment l'hypothèse selon laquelle le mécanisme de transport est le même pour les deux substances.

Zusammenfassung

Bei Meerschweinchen wurde der Übertritt von D-Isoascorbinsäure und von L-Ascorbinsäure verglichen. Saturationsphänomene werden gezeigt. Ein viel höherer Plasmaspiegel ist erforderlich für D-Isoascorbinsäure als für Ascorbinsäure, um ein Saturationsniveau im Kammerwasser zu erreichen. Die Affinität von Ascorbinsäure zum Transportsubstrat wird 4–5 mal höher geschätzt als jene für D-Isoacorbinsäure. Die Resultate stehen in Überein-stimmung mit der Annahme, daß der Transportmechanismus für beide Substanzen der gleiche ist.

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Copyright information

© Dr. W. Junk N.V. 1969

Authors and Affiliations

  • Erik Linnér
    • 1
    • 2
  • Karin Nordström
    • 1
    • 2
  1. 1.Department of OphthalmologyUniversity of Ume»Ume»
  2. 2.Department of PharmacologyUniversity of UppsalaUppsala

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