The stoichiometry of the exchange catalysed by the mitochondrial calcium/sodium antiporter.
نویسنده
چکیده
Rat heart mitochondria respiring on succinate in the presence of Ruthenium Red (to inhibit uptake on the Ca2+ uniporter) released Ca2+ on the calcium/sodium antiporter until a steady state was reached. Addition of the ionophore A23187 (which catalyses Ca2+/2H+ exchange) did not perturb this steady state. Thermodynamic analysis showed that if a Ca2+/nNa+ exchange with any value of n other than 2 was at equilibrium, addition of A23187 would cause an obvious change in extramitochondrial free [Ca2+]. Therefore the endogenous calcium/sodium antiporter of mitochondria catalyses electroneutral Ca2+/2Na+ exchange.
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 229 1 شماره
صفحات -
تاریخ انتشار 1985