Transient state kinetic studies of Ca2+-dependent atpase and Ca translocation by cardiac sarcoplasmic reticulum. Role of the 22,000-dalton protein phospholamban

1980 ◽  
Vol 45 (2) ◽  
pp. 415
Author(s):  
M. Tada ◽  
M. Yamada ◽  
F. Ohmori ◽  
T. Kuzuya ◽  
M. Inui ◽  
...  
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Transient State ◽  
Kinetic Studies ◽  
Cardiac Sarcoplasmic Reticulum ◽  
Dependent Atpase ◽  
State Kinetic

Transient state kinetic studies of phosphorylation by ATP and Pi of the calcium-dependent ATPase from sarcoplasmic reticulum

1979 ◽  
Vol 568 (2) ◽  
pp. 437-445 ◽  
Author(s):  
Adalberto Vieyra ◽  
Helena Maria Scofano ◽  
Horácio Guimarães-Motta ◽  
Ronald K. Tume ◽  
Leopoldo De Meis
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Transient State ◽  
Kinetic Studies ◽  
Calcium Dependent ◽  
Dependent Atpase ◽  
State Kinetic

scholarly journals Differences in Ca2+-management between the ventricle of two species of neotropical teleosts: the jeju, Hoplerythrinus unitaeniatus (Spix & Agassiz, 1829), and the acara, Geophagus brasiliensis (Quoy & Gaimard, 1824)

2009 ◽  
Vol 7 (3) ◽  
pp. 471-478 ◽  
Author(s):  
Monica Jones Costa ◽  
Francisco Tadeu Rantin ◽  
Ana Lúcia Kalinin
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Physiological Role ◽  
Stimulation Frequency ◽  
Cardiac Sarcoplasmic Reticulum ◽  
Heart Frequency ◽  
Geophagus Brasiliensis ◽  
Hoplerythrinus Unitaeniatus

This study analyzed the physiological role of the cardiac sarcoplasmic reticulum (SR) of two neotropical teleosts, the jeju, Hoplerythrinus unitaeniatus (Erythrinidae), and the acara, Geophagus brasiliensis (Cichlidae). While the in vivo heart frequency (fH - bpm) of acara (79.6 ± 6.6) was higher than that of the jeju (50.3 ± 2.7), the opposite was observed for the ventricular inotropism (Fc - mN/mm²) at 12 bpm (acara = 28.66 ± 1.86 vs. jeju = 36.09 ± 1.67). A 5 min diastolic pause resulted in a strong potentiation of Fc (≅ 90%) of strips from jeju, which was completely abolished by ryanodine. Ryanodine also resulted in a ≅ 20% decrease in the Fc developed by strips from jeju at both subphysiological (12 bpm) and physiological (in vivo) frequencies. However, this effect of ryanodine reducing the Fc from jeju was completely compensated by adrenaline increments (10-9 and 10-6 M). In contrast, strips from acara were irresponsive to ryanodine, irrespective of the stimulation frequency, and increases in adrenaline concentration (to 10-9 and 10-6 M) further increased Fc. These results reinforce the hypothesis of the functionality of the SR as a common trait in neotropical ostariophysian (as jeju), while in acanthopterygians (as acara) it seems to be functional mainly in 'athletic' species.

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