A tumour of the Adrenal medulla (Pheochromocytoma) is associated with an increased production of which hormon… - AIIMS Jodhpur SNO-2023

AIIMS Jodhpur SNO-2023

Applied Physiology

Easy

Appeared in: AIIMS Jodhpur SNO-2023

Explanation

Pheochromocytoma is a tumor of the chromaffin cells located in the adrenal medulla.
The adrenal medulla's primary function is to synthesize and secrete catecholamines.
Epinephrine (adrenaline) and norepinephrine (noradrenaline) are the main catecholamines produced.
Therefore, a pheochromocytoma leads to an overproduction of epinephrine, causing symptoms of sympathetic nervous system overactivity.

Option A: Glucocorticoids, such as cortisol, are steroid hormones produced by the zona fasciculata of the adrenal cortex, not the medulla.
Option B: Mineralocorticoids, primarily aldosterone, are produced by the zona glomerulosa of the adrenal cortex.
Option C: Androgens (sex hormones) are produced by the zona reticularis of the adrenal cortex.

Visual 1: Diagram - An illustration of the adrenal gland, clearly labeling the outer cortex (with its three zones: glomerulosa, fasciculata, reticularis) and the inner medulla. This helps visualize the origin of different hormones.
Visual 2: Flowchart - A simple flowchart showing how a pheochromocytoma in the adrenal medulla leads to increased epinephrine secretion, resulting in the classic triad of symptoms: palpitations, headache, and diaphoresis.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Hormone secretion by adrenal gland tumors as background academic context rather than a clinical decision trigger.
The hallmark sign of pheochromocytoma is severe, often paroxysmal (episodic), hypertension. Nurses must be vigilant in monitoring blood pressure to prevent a life-threatening hypertensive crisis.
A critical patient safety measure is to strictly avoid palpating the abdomen of a patient with suspected or confirmed pheochromocytoma. This action can trigger a massive release of catecholamines, leading to a sudden and severe spike in blood pressure.
What if? If a patient presented with central obesity, a 'moon face,' and purple striae on the abdomen, the suspected diagnosis would shift from pheochromocytoma to Cushing's syndrome. The investigation would then focus on the adrenal cortex and excess production of glucocorticoids (cortisol), not epinephrine.

How to Approach the Question

First, identify the key anatomical location mentioned in the question: the 'Adrenal medulla'.
Next, identify the specific pathology: 'Pheochromocytoma'.
Recall the basic physiology of the adrenal gland, differentiating the hormones produced by the outer cortex from those produced by the inner medulla.
Associate the adrenal medulla with the production of catecholamines (epinephrine and norepinephrine).
Connect the pathology (Pheochromocytoma) with its location (medulla) to deduce that the tumor will cause an overproduction of the hormones made in that area.
Scan the options to find the hormone that is a catecholamine produced by the adrenal medulla. Epinephrine is the correct choice.

Concept Tested & Keywords

Concept Tested: Hormone secretion by adrenal gland tumors
Stem keywords: tumour, Adrenal medulla, Pheochromocytoma, increased production, hormone
Lead-in keywords: which hormone
Clinical cues: The location of the tumor (Adrenal medulla) is the key to identifying the hormone involved.

QF7F2_yWMquzWNIoEIydlc