Sodium-dependent and calcium-dependent calcium transport by rat brain microsomes.

  title={Sodium-dependent and calcium-dependent calcium transport by rat brain microsomes.},
  author={Gerard D. Schellenberg and Phillip D. Swanson},
  journal={Biochimica et biophysica acta},
  volume={648 1},
Microsomal vesicles prepared from rat brain contain a Na+-Ca2+ exchange transport system capable of accumulating Ca2+ in a time- and temperature-dependent manner. The Ca2+ accumulated by these vesicles was released by the Ca2+ ionophore A23187 but not by EGTA. The Km value for Ca2+ uptake was 23 microM with a maximal velocity of 21 nmol Ca2+/mg per min. Ca2+ uptake was significantly inhibited by La3+, Sr2+, Mn2+ and Ba2+ and to a lesser extent by Mg2+. 45Ca2+ accumulated by Na+-dependent uptake… CONTINUE READING