IOVS Archives of Disease in Childhood
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (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
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Burke, J. M.
Right arrow Articles by Twining, S. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Burke, J. M.
Right arrow Articles by Twining, S. S.

Investigative Ophthalmology & Visual Science, Vol 29, 1789-1793, Copyright © 1988 by Association for Research in Vision and Ophthalmology

ARTICLES AND REPORTS

Regional comparisons of cathepsin D activity in bovine retinal pigment epithelium

JM Burke and SS Twining
Department of Ophthalmology, Medical College of Wisconsin, Milwaukee 53226.

Cathepsin D is the lysosomal protease in the retinal pigment epithelium which is presumed to be the major enzyme involved in the degradation of shed discs during the photoreceptor renewal process. In this study, the cathepsin D activity in RPE cells from the posterior area centralis was compared to the activity in cells from the equatorial region of the same bovine eyes. Enzyme activities were measured both in paired fresh RPE isolates from the two retinal regions and in paired regional RPE cultures. Cultures were further analyzed for changes in enzyme activity with time in vitro from 3 to 11 weeks. Analysis of freshly isolated RPE cells from 30 eyes indicated that cells from the area centralis have significantly higher cathepsin D activity than cells from the more peripheral retina. Paired cultures of RPE from the two regions did not express the intraeye topographical differences in enzyme activity which were observed in fresh isolates. There were significant variations in enzyme activity in cultured RPE cells with time in vitro, but activity levels did not show progressive increases or decreases with in vitro aging. After 11 weeks in vitro, but not at earlier times, the enzyme activities in the paired regional cultures from the same eye were highly correlated. The data suggest that the higher levels of cathepsin D activity observed in the freshly isolated RPE from the area centralis result from modulators of enzyme activity which are not present in culture.


This article has been cited by other articles:


Home page
 Mol. Interv.Home page
J. M. Burke and L. M. Hjelmeland
MOSAICISM OF THE RETINAL PIGMENT EPITHELIUM: seeing the small picture
Mol. Interv., August 1, 2005; 5(4): 241 - 249.
[Abstract] [Full Text] [PDF]

Home page
 Physiol. Rev.Home page
O. Strauss
The Retinal Pigment Epithelium in Visual Function
Physiol Rev, July 1, 2005; 85(3): 845 - 881.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1988 by the Association for Research in Vision and Ophthalmology