Aldosterone is secreted by the \ \ \ \ \ \ \ gland? - DSSSB - 29 August 2019 (Shift-2)

DSSSB - 29 August 2019 (Shift-2)

Applied Anatomy

Easy

Appeared in: DSSSB - 29 August 2019 (Shift-2)

Explanation

Aldosterone is a primary mineralocorticoid hormone essential for life.
It is synthesized and secreted by the zona glomerulosa, the outermost layer of the adrenal cortex, which sits atop the kidneys.
Its main function is to regulate the balance of sodium and potassium in the body, which directly impacts blood volume and blood pressure.
The secretion of aldosterone is primarily regulated by the Renin-Angiotensin-Aldosterone System (RAAS).

Option B: The thyroid gland's primary role is to regulate metabolism through its hormones, thyroxine (T4) and triiodothyronine (T3), and to regulate blood calcium through calcitonin. It is not involved in aldosterone production.
Option C: The pituitary gland, while being the 'master gland', does not directly secrete aldosterone. It secretes Adrenocorticotropic Hormone (ACTH), which stimulates the adrenal cortex to produce cortisol, but has a lesser effect on aldosterone secretion.
Option D: The pineal gland's function is linked to circadian rhythms. It secretes melatonin in response to darkness, helping to regulate sleep-wake cycles.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Hormone secretion by endocrine glands as background academic context rather than a clinical decision trigger.
Understanding aldosterone's source is crucial for diagnosing and managing conditions like Conn's syndrome (primary hyperaldosteronism), characterized by hypertension and hypokalemia, and Addison's disease (adrenal insufficiency), which involves aldosterone deficiency leading to hypotension and hyperkalemia.
Nurses monitor blood pressure, serum sodium, and potassium levels in patients with suspected adrenal disorders. They also administer medications like spironolactone (an aldosterone antagonist) or fludrocortisone (a synthetic mineralocorticoid).
What if? - If a patient on an ACE inhibitor (which blocks part of the RAAS) develops high potassium levels (hyperkalemia), the nurse should recognize this as a potential adverse effect. The drug reduces aldosterone secretion, which in turn decreases potassium excretion.

How to Approach the Question

First, identify the key term in the question, which is 'Aldosterone'.
Access your knowledge of the endocrine system and recall the specific functions and origins of major hormones.
Mentally link Aldosterone to its primary function: regulating salt and water balance, which affects blood pressure.
Recall which gland is responsible for this function. Aldosterone is a 'mineralocorticoid', produced by the adrenal 'cortex'.
Evaluate the given options: Adrenal, Thyroid, Pituitary, Pineal.
Select 'Adrenal' as it is the direct source of aldosterone. Eliminate the other options by recalling the primary hormones they produce (thyroid hormones, pituitary 'master' hormones, melatonin).

Concept Tested & Keywords

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