scholarly journals Optical Mapping of Intra-Sarcoplasmic Reticulum Ca2+ and Transmembrane Potential in the Langendorff-perfused Rabbit Heart

10.3791/53166 ◽  
2015 ◽  
Author(s):  
Lianguo Wang ◽  
Nicole M. De Jesus ◽  
Crystal M. Ripplinger
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Transmembrane Potential ◽  
Optical Mapping ◽  
Rabbit Heart ◽  
Perfused Rabbit Heart

scholarly journals Regulation of the Ca 2+ Gradient Across the Sarcoplasmic Reticulum in Perfused Rabbit Heart

1998 ◽  
Vol 83 (9) ◽  
pp. 898-907 ◽  
Author(s):  
Weina Chen ◽  
Robert London ◽  
Elizabeth Murphy ◽  
Charles Steenbergen
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Rabbit Heart ◽  
Perfused Rabbit Heart

scholarly journals Illumination-Induced Changes in Action Potential during Optical Mapping in Langendorff-Perfused Rabbit Heart

2013 ◽  
Vol 104 (2) ◽  
pp. 337a
Author(s):  
Ruta Vosyliute ◽  
Arvydas Matiukas ◽  
Irma Martišienė ◽  
Jonas Jurevičius ◽  
Antanas Navalinskas ◽  
...  
Keyword(s):  
Action Potential ◽  
Optical Mapping ◽  
Rabbit Heart ◽  
Perfused Rabbit Heart ◽  
Induced Changes

scholarly journals Role of Reduced Sarco-Endoplasmic Reticulum Ca2+-ATPase Function on Sarcoplasmic Reticulum Ca2+ Alternans in the Intact Rabbit Heart

2021 ◽  
Vol 12 ◽  
Author(s):  
Lianguo Wang ◽  
Rachel C. Myles ◽  
I-Ju Lee ◽  
Donald M. Bers ◽  
Crystal M. Ripplinger
Keyword(s):  
Endoplasmic Reticulum ◽  
Sarcoplasmic Reticulum ◽  
Optical Mapping ◽  
Cyclopiazonic Acid ◽  
Rabbit Heart ◽  
Intracellular Ca ◽  
Cardiac Alternans ◽  
Intact Rabbit ◽  
Rapid Ventricular Pacing ◽  
Serca Inhibition

Sarcoplasmic reticulum (SR) Ca2+ cycling is tightly regulated by ryanodine receptor (RyR) Ca2+ release and sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) Ca2+ uptake during each excitation–contraction coupling cycle. We previously showed that RyR refractoriness plays a key role in the onset of SR Ca2+ alternans in the intact rabbit heart, which contributes to arrhythmogenic action potential duration (APD) alternans. Recent studies have also implicated impaired SERCA function, a key feature of heart failure, in cardiac alternans and arrhythmias. However, the relationship between reduced SERCA function and SR Ca2+ alternans is not well understood. Simultaneous optical mapping of transmembrane potential (Vm) and SR Ca2+ was performed in isolated rabbit hearts (n = 10) using the voltage-sensitive dye RH237 and the low-affinity Ca2+ indicator Fluo-5N-AM. Alternans was induced by rapid ventricular pacing. SERCA was inhibited with cyclopiazonic acid (CPA; 1–10 μM). SERCA inhibition (1, 5, and 10 μM of CPA) resulted in dose-dependent slowing of SR Ca2+ reuptake, with the time constant (tau) increasing from 70.8 ± 3.5 ms at baseline to 85.5 ± 6.6, 129.9 ± 20.7, and 271.3 ± 37.6 ms, respectively (p < 0.05 vs. baseline for all doses). At fast pacing frequencies, CPA significantly increased the magnitude of SR Ca2+ and APD alternans, most strongly at 10 μM (pacing cycle length = 220 ms: SR Ca2+ alternans magnitude: 57.1 ± 4.7 vs. 13.4 ± 8.9 AU; APD alternans magnitude 3.8 ± 1.9 vs. 0.2 ± 0.19 AU; p < 0.05 10 μM of CPA vs. baseline for both). SERCA inhibition also promoted the emergence of spatially discordant alternans. Notably, at all CPA doses, alternation of SR Ca2+ release occurred prior to alternation of diastolic SR Ca2+ load as pacing frequency increased. Simultaneous optical mapping of SR Ca2+ and Vm in the intact rabbit heart revealed that SERCA inhibition exacerbates pacing-induced SR Ca2+ and APD alternans magnitude, particularly at fast pacing frequencies. Importantly, SR Ca2+ release alternans always occurred before the onset of SR Ca2+ load alternans. These findings suggest that even in settings of diminished SERCA function, relative refractoriness of RyR Ca2+ release governs the onset of intracellular Ca2+ alternans.

scholarly journals Measurement of Free Ca in Sarcoplasmic Reticulum in Perfused Rabbit Heart Loaded with 1,2-Bis(2-amino-5,6-difluorophenoxy)ethane-N,N,N′,N′-tetraacetic Acid by F NMR

1996 ◽  
Vol 271 (13) ◽  
pp. 7398-7403 ◽  
Author(s):  
Weina Chen ◽  
Charles Steenbergen ◽  
Louis A. Levy ◽  
Joseph Vance ◽  
Robert E. London ◽  
...  
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Rabbit Heart ◽  
Tetraacetic Acid ◽  
Perfused Rabbit Heart

High-resolution1H NMR imaging of regional ischemia in the isolated perfused rabbit heart at 4.7 T

1991 ◽  
Vol 21 (1) ◽  
pp. 144-150 ◽  
Author(s):  
John C. Chatham ◽  
Stacey Ackerman ◽  
Stephen J. Blackband
Keyword(s):  
Rabbit Heart ◽  
Nmr Imaging ◽  
Regional Ischemia ◽  
Perfused Rabbit Heart
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