Regulated release of Ca2+ from respiring mitochondria by Ca2+/2H+ antiport.

摘要: Simultaneous measurements of oxygen consumption and transmembrane transport Ca2+, H+, phosphate show that the efflux Ca2+ from respiring tightly coupled rat liver mitochondria takes place by an electroneutral Ca2+/2H+ antiport process is ruthenium red-insensitive regulated oxidation-reduction state mitochondrial pyridine nucleotides. When nucleotides are kept in a reduced steady state, inhibited; when they oxidized activated. These processes were demonstrated allowing phosphate-depleted on succinate presence rotenone to take up medium. Upon subsequent addition red block via electrophoretic influx pathway, acetoacetate, bring into H+ ensued. The observed influx/Ca2+ ratio was close value 2.0 predicted for operation electrically neutral process.