In depression, there is deficiency of:

AIIMS Nagpur NO- 2020

Mental Health Nursing

Easy

Appeared in: AIIMS Nagpur NO- 2020

Explanation

5-HT, which is the chemical name for serotonin (5-hydroxytryptamine).
According to the monoamine hypothesis, depression is primarily associated with a deficiency of monoamine neurotransmitters in the brain.
Among the monoamines, serotonin (5-HT) is the most prominently linked to depression, playing a key role in mood regulation.
The effectiveness of Selective Serotonin Reuptake Inhibitors (SSRIs), which increase the availability of serotonin in the brain, provides strong evidence for this link.

Option A: While reduced dopamine activity can contribute to specific symptoms of depression, such as anhedonia (loss of pleasure) and lack of motivation, it is not considered the primary or most common neurotransmitter deficiency.
Option B: Acetylcholine is primarily involved in cognitive functions like memory and learning, as well as muscle control. It is not a monoamine and is not directly implicated in the primary pathophysiology of depression.
Option C: GABA is the main inhibitory neurotransmitter in the central nervous system. While some studies show reduced GABA levels in depression, its deficiency is more strongly and primarily associated with anxiety disorders, seizures, and insomnia.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Neurochemical basis of depression as background academic context rather than a clinical decision trigger.
This concept is the foundation for psychopharmacology in nursing. Nurses must understand it to educate patients on why they are taking antidepressants and how they work, which improves medication adherence.
Nurses monitor for both the therapeutic effects (improved mood, energy) and side effects (e.g., gastrointestinal upset, sexual dysfunction from SSRIs) of these medications, which are directly related to their impact on neurotransmitter levels.
What if? A patient on an SSRI for 8 weeks shows no improvement. The nurse should anticipate that the provider might consider switching to a different class of antidepressant, such as an SNRI (Serotonin-Norepinephrine Reuptake Inhibitor) or one that also affects dopamine, acknowledging that different neurotransmitters may be involved in that individual's depression.

How to Approach the Question

First, identify the core of the question, which is asking about the specific neurochemical deficiency linked to depression.
Recall the main biological theory of depression: the monoamine hypothesis.
The monoamine hypothesis states that depression is linked to low levels of three key neurotransmitters: serotonin, norepinephrine, and dopamine.
Evaluate the given options. 5-HT is the chemical name for serotonin.
Recognize that while dopamine and GABA can be involved, serotonin (5-HT) is considered the most central and primary neurotransmitter in the pathophysiology of depression, making it the best answer.
Eliminate acetylcholine as it is not a monoamine and is primarily associated with cognitive and muscular functions.

Concept Tested & Keywords

Q_uI3roJPk7VMgIF3qh2Tn

E6 Kaplan Sadock's Synopsis of Psychiatry-2022 (pp 1-3768 of 3768) pp. 1268-1270, 1269-1271