Activation of calcium transport in skeletal muscle sarcoplasmic reticulum by monovalent cations.
نویسندگان
چکیده
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+.
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 251 22 شماره
صفحات -
تاریخ انتشار 1976