Abstract
Effects of cycloheximide and aldosterone, alone or in combination, on kidney, liver and blood carbonic anhydrase activity, kidney Na+-K+-ATPase activity and on urinary excretion of sodium were investigated using normal and adrenalectomized mice to clarify the significance of above enzymes as a mediator of action of aldosterone on sodium excretion.
1. In normal mice, cycloheximide decreased kidney and blood carbonic anhydrase activity. The inhibition rates are parallel with the increase of doses and the maximum effect was observed at 4 hr after treatment. Liver carbonic anhydrase and kidney ATPase activities were not affected by cycloheximide.
2. In adrenalectomized mice, combined administration of cycloheximide inhibited the aldosterone-induced increase of kidney carbonic anhydrase activity and decrease of urinary excretion of 22Na. Kidney ATPase activity was unaltered in above condition.
3. In adrenalectomized mice, single injection of cycloheximide did not affect the enzyme activity and sodium excretion.
