The Effect of $Mg^#$, $Ca^#$, $Na^+$, $K^+$ and Creatine Phosphate on the ATPase Activity of Microsomal Fraction from Rabbit Uterus

가토자궁근(家兎子宮筋)에서 분리(分離)한 Microsome 분획내(分劃內) Adenosinetriphosphatase 활성도(活性度)에 미치는 $Mg^#$, $Ca^#$, $Na^+$, $K^+$ 및 Creatine phosphate의 영향(影響)

The author investigated the effect of $Mg^#$, $Ca^#$, $Na^+$, $K^+$ and creatine phosphate on the ATPase activity of microsomal fraction isolated from rabbit uterus and obtained the following results : 1) The uterine microsomal fraction contained the $Na^+-$ and $K^+-$ activated ATPase in the presence of $Mg^#$. The ATPase activity increased with protein content in the fraction. 2) The maximum ATPase activity was obtained at $Na^+$ and $K^+$ concentraction of 100 mM respectively. 3) In the absence of $Mg^#$, the ATPase was not activated by $Na^+$ and $K^+$, but inhibited. 4) Car stimulated the $Na^+-$ and $K^+-$ activated ATPase in the presence of $Mg^#$. However, in the absence of $Mg^#$, the ATPase was not activated by $Ca^#$. 5) The $K^+-$ activated ATPase activity was greater than the $Na^+-activated$ ATPase under all conditions. 6) The $Na^+-$ and $K^+$ activated ATPase activity was increased by addition of creatine phosphokinase and creatine phosphate to the reaction mixture.