Chronic intraocular pressure elevation impairs autoregulatory capacity in streptozotocin-induced diabetic rat retina

Wong, Vickie H., Armitage, James A., He, Zheng, Hui, Flora, Vingrys, Algis J. and Bui, Bang V. 2015, Chronic intraocular pressure elevation impairs autoregulatory capacity in streptozotocin-induced diabetic rat retina, Ophthalmic and physiological optics, vol. 35, no. 2, pp. 125-134, doi: 10.1111/opo.12174.

Attached Files
Name Description MIMEType Size Downloads

Title Chronic intraocular pressure elevation impairs autoregulatory capacity in streptozotocin-induced diabetic rat retina
Author(s) Wong, Vickie H.
Armitage, James A.ORCID iD for Armitage, James A.
He, Zheng
Hui, Flora
Vingrys, Algis J.
Bui, Bang V.
Journal name Ophthalmic and physiological optics
Volume number 35
Issue number 2
Start page 125
End page 134
Total pages 10
Publisher Wiley
Place of publication London, Eng.
Publication date 2015-03-01
ISSN 0275-5408
Keyword(s) Blood flow
Intraocular pressure
Summary Purpose: To assess ocular blood flow responses to acute IOP stress following 4 weeks of chronic IOP elevation in streptozotocin (STZ)-induced diabetic and control rats. We hypothesise that chronic IOP elevation for 4 weeks will further impair blood flow regulation in STZ-induced diabetic rats eyes. Methods: Two weeks following citrate buffer or STZ-injections chronic IOP elevation was induced in Long Evans rats via fortnightly intracameral injections of microspheres (15 μm) suspended in 5% polyethylene glycol. IOP was monitored daily. Electroretinography (ERG, -6.79-2.07 log cd s m-2) was undertaken at Week 4 to compare photoreceptor (RmPIII), ON-bipolar cell (Vmax) and ganglion cell dominant ERG [scotopic threshold response (STR)] components. 4 weeks post-chronic IOP induction, ocular blood flow (laser Doppler flowmetry) was measured in response to acute IOP challenge (10-100 mmHg, in 5 mmHg steps, each 3 min). Results: Four weeks of chronic IOP (mean ± S.E.M., citrate: 24.0 ± 0.3 to 30.7 ± 1.3 and STZ-diabetes: 24.2 ± 0.2 to 31.1 ± 1.2 mmHg) was associated with reduced photoreceptor amplitude in both groups (-25.3 ± 2.2% and -17.2 ± 3.0%, respectively). STZ-diabetic eyes showed reduced photoreceptor sensitivity (citrate: 0.5 ± 1.8%, STZ-diabetic: -8.1 ± 2.4%). Paradoxically ON-bipolar cell sensitivity was increased, particularly in citrate control eyes (citrate: 166.8 ± 25.9%, STZ-diabetic: 64.8 ± 18.7%). The ganglion cell dominant STR was not significantly reduced in STZ-diabetic rats. Using acute IOP elevation to probe autoregulation, we show that STZ-diabetes impaired autoregulation compared with citrate control animals. The combination of STZ-diabetes and chronic IOP elevation further impaired autoregulation. Conclusions: STZ-diabetes and chronic IOP elevation appear to be additive risk factors for impairment of ocular blood flow autoregulation.
Language eng
DOI 10.1111/opo.12174
Field of Research 111303 Vision Science
110306 Endocrinology
Socio Economic Objective 920104
HERDC Research category C1 Refereed article in a scholarly journal
ERA Research output type C Journal article
Grant ID GNT 1046203
Copyright notice ©2015, Wiley
Persistent URL

Document type: Journal Article
Collection: School of Medicine
Connect to link resolver
Unless expressly stated otherwise, the copyright for items in DRO is owned by the author, with all rights reserved.

Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 1 times in TR Web of Science
Scopus Citation Count Cited 1 times in Scopus
Google Scholar Search Google Scholar
Access Statistics: 545 Abstract Views, 2 File Downloads  -  Detailed Statistics
Created: Mon, 13 Apr 2015, 12:38:27 EST

Every reasonable effort has been made to ensure that permission has been obtained for items included in DRO. If you believe that your rights have been infringed by this repository, please contact