4.
The mercurial mersalyl has little effect either on rapid Mg
++ binding by isolated rat liver mitochondria or on the total Mg
++ content of these organelles measured after 0.75 min of incubation at 20°C. The data do not support the previous suggestion that the increased permeability to K
+ of mitochondria treated with mersalyl results from release of endogenous Mg
++. An increased pH-dependence of unidirectional Mg
++ flux into respiring rat liver mitochondria is suggested to arise indirectly from inhibition by mersalyl of pH shifts associated with exchanges of endogenous phosphate. In addition, mersalyl appears to have a stimulatory effect on Mg
++ influx. Mersalyl also increases the average rate of unidirectional efflux of endogenous Mg
++. The stimulatory effects of mersalyl on Mg
++ flux are similar to, although quantitatively less than, the previously reported effects of mersalyl on mitochondrial K
+ flux.
相似文献