Ca2+-sparks and Ca2+-signals in retinal arterioles
Author Information
Author(s): James Tumelty, Norman Scholfield, Michael Stewart, Tim Curtis, Graham McGeown
Primary Institution: The Queen's University of Belfast
Hypothesis
Spontaneous Ca2+-events in retinal arterioles result from activation of ryanodine receptors in the sarcoplasmic reticulum.
Conclusion
The study demonstrates that Ca2+-sparks serve as building blocks for global Ca2+-signals in retinal arterioles.
Supporting Evidence
- Spontaneous Ca2+-sparks were observed to spread across the width of retinal arteriolar myocytes.
- Application of cyclopiazonic acid increased spark frequency and oscillation amplitude initially.
- Ryanodine and tetracaine reduced the frequency of sparks and oscillations.
- Nifedipine reduced both spark and oscillation frequency and amplitude.
- Removal of external calcium reduced the frequency of sparks and oscillations.
Takeaway
This study found that tiny bursts of calcium in retinal blood vessel cells can combine to create bigger signals that help control blood flow.
Methodology
Spontaneous Ca2+-events were imaged in myocytes within intact retinal arterioles isolated from rat eyes using confocal Ca2+-imaging.
Limitations
The study was limited to a specific type of retinal arterioles and may not generalize to other vascular tissues.
Participant Demographics
Male Sprague–Dawley rats (200–300 g) were used for the experiments.
Statistical Information
P-Value
p<0.0001
Statistical Significance
p<0.05
Digital Object Identifier (DOI)
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