Abstract
The rates of calcium transport and Ca2+-dependent ATP hydrolysis by rabbit skeletal muscle sarcoplasmic reticulum were stimulated by monovalent cations. The rate of decomposition of phosphoprotein intermediate of the Ca2+-dependent ATPase of sarcoplasmic reticulum was also increased by these ions to an extent that is sufficient to account for the stimulation of calcium transport and Ca2+-dependent ATPase activity. The order of effectiveness of monovalent cations tested at saturating concentrations in increasing rate of phosphoprotein decomposition is: K+, Na+ greater than Rb+, NH4+ greater than Cs+ greater than Li+, choline+, Tris+.
Publication types
-
Research Support, U.S. Gov't, Non-P.H.S.
-
Research Support, U.S. Gov't, P.H.S.
MeSH terms
-
Adenosine Triphosphatases / metabolism
-
Ammonia / pharmacology
-
Animals
-
Biological Transport, Active / drug effects
-
Calcium / metabolism*
-
Cations, Monovalent*
-
Cesium / pharmacology
-
Choline / pharmacology
-
Kinetics
-
Lithium / pharmacology
-
Microsomes / metabolism
-
Muscles / metabolism*
-
Phosphoproteins / metabolism
-
Potassium / pharmacology
-
Rabbits
-
Rubidium / pharmacology
-
Sarcoplasmic Reticulum / drug effects
-
Sarcoplasmic Reticulum / metabolism*
-
Sodium / pharmacology
-
Tromethamine / pharmacology
Substances
-
Cations, Monovalent
-
Phosphoproteins
-
Tromethamine
-
Cesium
-
Ammonia
-
Lithium
-
Sodium
-
Adenosine Triphosphatases
-
Rubidium
-
Choline
-
Potassium
-
Calcium