the renal tubules blocking the synthesis of aldosterone induced proteins (AIP)
Spironolactone acts as an aldosterone antagonist by competitively binding to mineralocorticoid receptors in the distal convoluted tubule and collecting ducts of the nephron in the kidney. By binding to these receptors, spironolactone inhibits the action of aldosterone, leading to decreased expression of aldosterone-induced proteins (AIPs) such as the epithelial sodium channels (ENaC) and the Na+/K+ ATPase pump. This ultimately results in decreased sodium reabsorption and potassium retention, leading to diuresis and natriuresis while sparing potassium.