Which of the following is not a steroid hormone?

Appeared in: BSF Staff Nurse - 2021

Explanation

The question asks to identify the hormone that is NOT a steroid.
Relaxin is a peptide hormone, composed of amino acid chains and structurally similar to insulin.
Androgen, Aldosterone, and Estrogen are all steroid hormones, meaning they are derived from a cholesterol precursor.
Steroid hormones are lipid-soluble and act on intracellular receptors, whereas peptide hormones are water-soluble and act on cell surface receptors.

Option A: Androgens (e.g., testosterone) are a class of male sex hormones that are chemically classified as steroids, derived from cholesterol.
Option B: Aldosterone is a mineralocorticoid hormone produced by the adrenal cortex. It is a steroid hormone essential for sodium conservation in the kidney.
Option C: Estrogens are female sex hormones responsible for the development and regulation of the female reproductive system. They are steroid hormones.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Classification of Hormones (Steroid vs. Peptide) as background academic context rather than a clinical decision trigger.
Understanding the chemical class of hormones is crucial for nurses, as it dictates the route of administration, mechanism of action, and potential side effects of hormonal therapies (e.g., oral contraceptives, hormone replacement therapy).
Steroid-based medications are often lipid-soluble and can be administered orally or topically, while peptide hormones are typically proteins that would be digested if taken orally, requiring administration by injection.
What if the question was about which hormone is a glycoprotein? The answer might be Follicle-Stimulating Hormone (FSH) or Luteinizing Hormone (LH), which are also crucial in reproduction but belong to a different chemical class (glycoproteins) than steroids or simple peptides.

How to Approach the Question

First, identify the core of the question, which is to find the option that does not belong to the 'steroid hormone' category. The keyword 'NOT' is critical.
Review each option and recall or determine its chemical classification.
Think about the precursor molecule. Steroid hormones are synthesized from cholesterol.
Analyze Option A (Androgen), B (Aldosterone), and C (Estrogen). All are well-known examples of hormones derived from cholesterol, classifying them as steroids.
Analyze Option D (Relaxin). Recall that relaxin is a protein-based hormone involved in pregnancy, structurally similar to insulin.
Conclude that since Relaxin is a peptide (protein) hormone, it is the correct answer as it is not a steroid.

Concept Tested & Keywords

QuMAlLcwpjThI6Z2OWL3y6

E6 Pharmacology Katzung 16e p. 1138-1140

E6 Biochemistry U Satyanarayana— Part 2 (pp 421-820 of 840) p. 66-68

Practise the full BSF Staff Nurse - 2021

Attempt every question from this paper in a timed mock, then review the full solution for each one.