Excess secretion of aldosterone causes all except:
**Core Concept**
Aldosterone is a crucial mineralocorticoid hormone produced by the zona glomerulosa of the adrenal cortex. It plays a vital role in regulating electrolyte and water balance by promoting sodium retention and potassium excretion in the kidneys. Excess secretion of aldosterone can lead to various clinical manifestations.
**Why the Correct Answer is Right**
Excess secretion of aldosterone causes an increase in sodium reabsorption and potassium excretion in the distal convoluted tubules and collecting ducts of the kidneys. This results in:
* Hypokalemia (low potassium levels) due to increased potassium excretion
* Hypertension (high blood pressure) due to increased sodium reabsorption and subsequent fluid retention
* Metabolic alkalosis (elevated blood pH) due to increased hydrogen ion excretion
* Aldosterone also promotes the release of antidiuretic hormone (ADH), leading to water retention and further increasing blood volume.
**Why Each Wrong Option is Incorrect**
**Option A:** The statement is incorrect because hypokalemia is indeed a consequence of excess aldosterone secretion. This is due to the hormone's effect on increasing potassium excretion.
**Option B:** The statement is incorrect because hypertension is a well-established consequence of excess aldosterone secretion. The hormone promotes sodium retention and fluid expansion, leading to increased blood pressure.
**Option C:** The statement is incorrect because metabolic alkalosis is a known consequence of excess aldosterone secretion. The hormone promotes the excretion of hydrogen ions, leading to an increase in blood pH.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the effects of excess aldosterone secretion can be reversed with spironolactone, a potassium-sparing diuretic that antagonizes the effects of aldosterone.
**Correct Answer: A.**