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Updated: Jul 16, 2026
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Isolation of Retinal Arterioles for Ex Vivo Cell Physiology Studies
Published on: July 14, 2018
Calcium signaling in ocular arterioles
Tim M Curtis1, C Scholfield, Dr J Graham McGeown
1Centre of Vision Sciences, The Queen's University of Belfast, Institute of Clinical Sciences, The Royal Victoria Hospital, Grosvenor Road, Belfast, BT12 6BA, Northern Ireland.
Critical Reviews in Eukaryotic Gene Expression
|March 8, 2007
Summary
Calcium signaling in retinal arterioles controls blood flow to photoreceptors. This review details molecular mechanisms of calcium-ion (Ca2+) influx and release, and spontaneous Ca2+ signals in vascular smooth muscle.
Area of Science:
- Ophthalmology
- Vascular Physiology
- Cell Biology
Background:
- Local blood flow regulation in the retina is crucial for photoreceptor and neuron function.
- Vascular tone in choroidal and retinal arterioles, modulated by calcium ions ([Ca2+]), controls blood flow.
- Smooth muscle cell contraction and vascular constriction are regulated by intracellular [Ca2+].
Purpose of the Study:
- To review the cell physiology of calcium-signaling processes in retinal arterioles.
- To emphasize the molecular mechanisms underlying [Ca2+] regulation in vascular smooth muscle.
- To explore the role of [Ca2+] signaling heterogeneity in retinal vascular function.
Main Methods:
- Review of existing literature on calcium signaling pathways.
- High-speed confocal calcium imaging to visualize [Ca2+] dynamics.
- Analysis of spontaneous calcium events like sparks, waves, and oscillations.
Main Results:
- Calcium influx occurs through voltage-operated, store-operated, and receptor-operated channels.
- Intracellular calcium release involves Ryanodine Receptor (RyR) and Inositol Trisphosphate Receptor (IP3R) channels.
- Retinal arterioles exhibit heterogeneous [Ca2+] signals, including localized sparks and global waves/oscillations.
Conclusions:
- Understanding [Ca2+] signaling mechanisms is key to retinal blood flow regulation.
- Spontaneous [Ca2+] signals in retinal arterioles are complex and dynamic.
- Investigating the targeting of these signals in disease states offers future research avenues.
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