Deutsch
 
Hilfe Datenschutzhinweis Impressum
  DetailsucheBrowse

Datensatz

DATENSATZ AKTIONENEXPORT

Freigegeben

Zeitschriftenartikel

Comparison between strontium and calcium uptake by the fragmented sarcoplasmic reticulum

MPG-Autoren
/persons/resource/persons211221

Mermier,  Pierre
Max Planck Institute for Medical Research, Max Planck Society;

/persons/resource/persons93324

Hasselbach,  Wilhelm
Emeritus Group Biophysics, Max Planck Institute for Medical Research, Max Planck Society;

Volltexte (beschränkter Zugriff)
Für Ihren IP-Bereich sind aktuell keine Volltexte freigegeben.
Volltexte (frei zugänglich)
Es sind keine frei zugänglichen Volltexte in PuRe verfügbar
Ergänzendes Material (frei zugänglich)
Es sind keine frei zugänglichen Ergänzenden Materialien verfügbar
Zitation

Mermier, P., & Hasselbach, W. (1976). Comparison between strontium and calcium uptake by the fragmented sarcoplasmic reticulum. European Journal of Biochemistry, 69(1), 79-86. doi:10.1111/j.1432-1033.1976.tb10860.x.


Zitierlink: https://hdl.handle.net/21.11116/0000-0002-C48F-0
Zusammenfassung
The ATP‐supported uptake of strontium by the fragmented sarcoplasmic reticulum is monophasic and proceeds more rapidly than the fast uptake of calcium. Strontium uptake is not activated by P4. The accumulation of strontium is nearly proportional to the external strontium concentration even in the millimolar range. Internal and external strontium quickly equilibrate. One mole of strontium is stored for every mole of ATP split by the Sr2+ ‐activated ATPase. In the absence of oxalate most of the strontium is taken up with a transport ratio of one. On the opposite, the transport ratio of calcium decreases immediately, especially when ADP is not instantaneously phosphorylated to ATP. In this case, energy, conversion is uncoupled more effectively by the simultaneous action of ADP and free internal calcium, resulting in the interruption of the fast uptake. After depletion of ATP most of the stored strontium is released and the remaining fraction appears to be not exchangeable. Strontium activates the slow uptake of calcium, but reduces the amplitude of the fast uptake. The calcium induced release of strontium, and vice versa, is partial and transient. The strontium activated ATPase does not transport calcium at low ionic calcium concentrations.