| Autor: |
van de Put FH; Department of Biochemistry, University of Nijmegen, The Netherlands., Visser GJ, Donkers EA, Theuvenet AP, Willems PH |
| Jazyk: |
angličtina |
| Zdroj: |
European journal of biochemistry [Eur J Biochem] 1993 Dec 15; Vol. 218 (3), pp. 959-62. |
| DOI: |
10.1111/j.1432-1033.1993.tb18453.x |
| Abstrakt: |
The potent inhibitor of Ca2+, Mg(2+)-ATPase activity, thapsigargin, has been used to investigate the effect of ambient free Ca2+ on basal Mg(2+)-dependent ATPase activity in rat liver microsomes. Thapsigargin non-competitively inhibited both Ca(2+)-stimulated ATP-dependent Ca2+ uptake and Ca(2+)-stimulated Mg(2+)-dependent ATPase activity. At a concentration of 1 microM, thapsigargin completely inhibited the Ca(2+)-pump activity, without affecting Mg(2+)-dependent ATPase activity measured in the absence of Ca2+. Increasing the ambient free Ca2+ concentration did not alter the basal Mg(2+)-dependent ATPase activity. The data presented indicate that ATPase activity measured in the absence of Ca2+ is a reliable measure for the basal Mg(2+)-dependent ATPase activity and that, consequently, the Ca(2+)-stimulated Mg(2+)-dependent ATPase activity can indeed be defined as the difference between the ATPase activity measured in the presence and the absence of Ca2+. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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