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The renin-angiotensin system and the developing retinal vasculature
Stella Sarlos1, Jennifer L Wilkinson-Berka
1Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia.
Investigative Ophthalmology & Visual Science
|February 25, 2005
Summary
The developing rat retina contains the renin-angiotensin system (RAS) in blood vessels and ganglion cells, potentially influencing early retinal vascularization. This system
Area of Science:
- Ophthalmology
- Physiology
- Developmental Biology
Background:
- The renin-angiotensin system (RAS) plays a crucial role in cardiovascular regulation.
- Understanding the RAS in ocular development is essential for identifying potential therapeutic targets.
Purpose of the Study:
- To investigate the localization and activity of RAS components in the developing rat retina.
- To determine if the RAS impacts retinal vascularization.
Main Methods:
- Utilized transgenic Ren-2 rats (overexpressing RAS) and Sprague-Dawley rats from postnatal day 1 to 90.
- Employed immunohistochemistry for RAS components and ACE, radioimmunoassay for renin activity, and autoradiography for ACE density.
- Administered ACE inhibitor lisinopril or AT(1) receptor antagonist losartan to assess effects on retinal vascularization.
Main Results:
- RAS components were consistently found in retinal blood vessels and ganglion cell layers.
- Ren-2 rats exhibited significantly higher retinal renin activity and more extensive peripheral vascularization compared to SD rats.
- ACE binding intensity increased with age, and while lisinopril reduced vascular density, losartan did not.
Conclusions:
- A complete RAS is present in the developing rat retina, primarily associated with blood vessels and ganglion cells.
- The study suggests the RAS may play a role in the early stages of retinal vascular development.
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