Ca2(+)- and Sr2(+)-sensitivity of the ATPase of myofibrils and natural actomyosins prepared from various muscles.
Ca2(+)- and Sr2(+)-sensitivity of myofibrils and natural actomyosins prepared from various kinds of muscles was investigated by examining the ATPase activity. Sr2+ at concentrations about 30 times higher than Ca2+ was required for activating the ATPase of myofibrils or natural actomyosins from fast skeletal, smooth and scallop striated muscles, while Sr2+ 8-13 times higher than Ca2+ was required for activating the slow skeletal or cardiac system. These findings were consistent with the previous report on the Ca2(+)- and Sr2(+)-sensitive superprecipitation of various natural actomyosins.
Shiraishi
F
F
Department of Clinical Pharmacology, Faculty of Medicine, Kyushu University, Fukuoka.
Ohtsuki
I
I
D000205:Actomyosin / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D049872:Bivalvia; D002118:Calcium / Q000494:pharmacology*; D002645:Chickens; D004789:Enzyme Activation / Q000187:drug effects; D009132:Muscles / Q000201:enzymology; D009210:Myofibrils / Q000201:enzymology*; D011817:Rabbits; D013324:Strontium / Q000494:pharmacology*; D013552:Swine
D000205:Actomyosin; D000251:Adenosine Triphosphatases; D002118:Calcium; D013324:Strontium