Which hormone is known as the “fight or flight” hormone?

Haryana CHO - 2022

Applied Physiology

Easy

Appeared in: Haryana CHO - 2022

Explanation

Adrenaline, also known as epinephrine, is released by the adrenal medulla in response to stimulation by the sympathetic nervous system.
It is the primary hormone responsible for the 'fight or flight' response, which prepares the body to face a threat or flee from danger.
The release of adrenaline causes physiological changes such as increased heart rate, elevated blood pressure, and mobilization of glucose from storage for immediate energy.
This response diverts blood flow to essential tissues like cardiac and skeletal muscles and away from non-essential areas like the gastrointestinal tract.

Option A: Progesterone is a steroid hormone primarily associated with the female reproductive system, specifically in regulating the menstrual cycle and maintaining pregnancy. It does not play a role in the acute stress response.
Option C: Glucagon is a hormone produced by the pancreas that raises blood glucose levels. While glucose is mobilized during the 'fight or flight' response, glucagon's primary role is to counteract insulin and manage blood sugar, not to initiate the overall stress response.
Option D: Aldosterone is a mineralocorticoid hormone produced by the adrenal cortex. Its main function is to regulate salt and water balance in the body, which influences long-term blood pressure control. It is not involved in the immediate 'fight or flight' reaction.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Hormonal regulation of the 'fight or flight' response as background academic context rather than a clinical decision trigger.
Nurses administer synthetic adrenaline (epinephrine) in critical situations such as cardiac arrest, anaphylactic shock, and severe asthma attacks to rapidly stimulate the heart, constrict blood vessels, and open airways.
Understanding the effects of adrenaline is vital for monitoring patients after its administration, as common side effects include tachycardia, hypertension, anxiety, and tremors.
What if? If a patient is taking a beta-blocker medication, their response to adrenaline may be significantly reduced. This is because beta-blockers block the very receptors that adrenaline needs to act on, particularly in the heart. A nurse should anticipate that a standard dose of epinephrine might be less effective in such a patient.

How to Approach the Question

First, identify the key phrase in the question: 'fight or flight' hormone. This is a well-known concept in physiology.
This is a factual recall question. Your task is to match the physiological response to the correct hormone.
Systematically review the function of each hormone listed in the options.
Progesterone is linked to pregnancy and the menstrual cycle.
Glucagon is linked to increasing blood sugar.
Aldosterone is linked to salt and water balance.

Concept Tested & Keywords

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