Silver ions trigger Ca2+ release by interaction with the (Ca2+-Mg2+)-ATPase in reconstituted systems.
It has been suggested that vesicles derived from the sarcoplasmic reticulum of skeletal muscle contain Ca2+ channels which can be opened by interaction with sulfhydryl reagents such as Ag+ or Hg2+. We show that, in reconstituted vesicles containing the (Ca2+-Mg2+)-ATPase purified from sarcoplasmic reticulum as the only protein, the ATPase can act as a pathway for Ca2+ efflux and that Ag+ induces a rapid release of Ca2+ from such reconstituted vesicles. We also show that Ag+ has a marked inhibitory effect on the ATPase activity of the purified ATPase. We suggest that the (Ca2+-Mg2+)-ATPase can act as a pathway for rapid Ca2+ release from sarcoplasmic reticulum.
D000818:Animals; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D005260:Female; D007700:Kinetics; D008081:Liposomes; D009132:Muscles / Q000378:metabolism; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D011817:Rabbits; D012519:Sarcoplasmic Reticulum / Q000378:metabolism*; D012834:Silver / Q000494:pharmacology*; D012835:Silver Nitrate / Q000494:pharmacology
D008081:Liposomes; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D012834:Silver; D012835:Silver Nitrate; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases; D002118:Calcium