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


     

A more recent version of this article appeared on July 1, 2008
 (Investigative Ophthalmology and Visual Science. )
© 2008 by The Association for Research in Vision and Ophthalmology, Inc.
doi:10.1167/iovs.07-1628
This Article
Right arrow Full Text (P<P[PDF])
Right arrow All Versions of this Article:
iovs.07-1628v1
49/7/3026    most recent
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 He, Z.
Right arrow Articles by Vingrys, A. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by He, Z.
Right arrow Articles by Vingrys, A. J.

Article

Effect of Repeated IOP Challenge on Rat Retinal Function

Zheng He 1*, Bang Viet Bui 2, and Algis J. Vingrys 3

1 Dept. of Optometry & Vision Sciences, The University of Melbourne, Cnr Kepple & Cardigan Street, Melbourne, Victoria, 3010, Australia
2 Optometry and Vision Sciences, University of Melbourne, Melbourne, Victoria, Australia
3 Optometry and Vision Sciences, The University of Melbourne, Melbourne, Victoria, Australia

* To whom correspondence should be addressed. E-mail: zhe{at}pgrad.unimelb.edu.au.


  Abstract

Purpose: To characterize the effect of repeated brief intraocular pressure (IOP) elevations and the effect of IOP fluctuation on retinal function. Methods: The effect of single, two and four episodes (70 mmHg, 15 min) are compared by defining the time course of functional recovery following insults. The effect of IOP variation is considered by comparing a constant with a varying insult, keeping a common IOP-time integral (single-60 vs. two-30 vs. four-15 min insults, 70 mmHg). IOP elevation is induced by anterior chamber cannulation in anesthetized, dark-adapted rats (n = 5-7/group). Electroretinograms (ERG) are recorded every 6 minutes throughout each event. Recovery time course is modeled using a logistic function and time for 50% recovery compared by non-parametric bootstrap. Results: ERG recovery becomes progressively slower with more IOP episodes, for bipolar cell and ganglion cell (p < 0.05), but not photoreceptor response (P > 0.05). In regards to IOP variation, bipolar cell recovery following four-15 min insults is faster than two-30 min insults (p < 0.05), which is faster than a single-60 min insult (p < 0.05). Ganglion cell recovery following the varying (both four-15 min and two-30 min) insult is faster than a constant (single-60 min) insult (p < 0.05). This improved recovery with varying IOP challenge is greater for bipolar cell than ganglion cell responses (p < 0.05). Conclusion: Repeated IOP insults lead to cumulative dysfunction in the inner retina. For the conditions used in this study, IOP variation per se is not detrimental but appears to be beneficial.

Key Words: intraocular pressure, electroretinography, ganglion cell, IOP fluctuation




This article has been cited by other articles:


Home page
 IOVSHome page
Y. X. Kong, J. G. Crowston, A. J. Vingrys, I. A. Trounce, and B. V. Bui
Functional Changes in the Retina during and after Acute Intraocular Pressure Elevation in Mice
Invest. Ophthalmol. Vis. Sci., December 1, 2009; 50(12): 5732 - 5740.
[Abstract] [Full Text] [PDF]


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