IOVS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

P<P, published online ahead of print April 30, 2008
(Investigative Ophthalmology and Visual Science. )
© 2008 by The Association for Research in Vision and Ophthalmology, Inc.
DOI:  10.1167/iovs.07-1660
This Article
Right arrow Full Text (P<P[PDF])
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Anderson, O. A.
Right arrow Articles by Marshall, J.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Anderson, O. A.
Right arrow Articles by Marshall, J.

Article

Human Transscleral Albumin Permeability and the Effect of Topographical Location and Donor Age

Owen Alexander Anderson 1*, Timothy L Jackson 2, Jasmin Singh 1, Ali A. Hussain 1, and John Marshall 1

1 Kings College London Department of Ophthalmology, The Rayne Institute, London, United Kingdom
2 Department of Ophthalmology, Kings College Hospital, London, United Kingdom

* To whom correspondence should be addressed. E-mail: anderson.owen{at}doctors.org.uk.


  Abstract

PURPOSE. To quantify the permeability coefficient of albumin across human sclera and to assess topographical and age-related variation. METHODS. Equatorial superotemporal scleral tissue from 15 donor eyes (mean age 60 years, range 39-84 years) was mounted in a modified Ussing chamber. Additional tissue was taken from the anterior and posterior superotemporal regions of 6 eyes, and equatorial superonasal, and inferotemporal regions of a further 6 eyes. Fluorescein isothiocyanate (FITC) labeled, 0.412 mM, bovine albumin was placed in one hemi-chamber facing the internal scleral surface, and the rate of trans-scleral flux was determined over 24 hours, at 25 °C, with a spectrophotometer. RESULTS. Permeability coefficient for equatorial superotemporal scleral tissue at 25 °C (± 1 SD) was 0.83 ± 0.50 x10-6 cm.s-1. The permeability coefficient adjusted for 37 °C (± 1 SD) was 1.43 ± 0.86 x10-6 cm.s-1. The effect of donor age was assessed for the fifteen equatorial superotemporal samples. Regression analysis showed a significant decline in scleral diffusion of albumin with increasing donor age (p = 0.0166). There was no significant difference in diffusion over the different topographical regions tested. Partition coefficient to albumin also showed a decline with increasing donor age (p = 0.001). CONCLUSIONS: The permeability and partition coefficients of human sclera both significantly decline with increasing donor age. Permeability coefficient shows no significant variation over the different topographical regions tested. The decrease in albumin permeability with increasing donor age may have pharmacokinetic implications when considering transscleral diffuson of high molecular weight compounds.

Key Words: collagen, drug penetration, drug delivery, extracellular matrix, pharmacokinetics






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Copyright © 2008 by the Association for Research in Vision and Ophthalmology