Canadian Health Information Management Association Practice Exam 2026 - Free CHIMA Practice Questions and Study Guide

Aldosterone plays a crucial role in regulating blood pressure primarily through its effects on sodium and potassium balance in the kidneys. When blood pressure decreases, the adrenal glands release aldosterone, which prompts the kidneys to reabsorb more sodium into the bloodstream. This reabsorption of sodium leads to increased water retention, raising blood volume and thereby contributing to an increase in blood pressure.

Furthermore, aldosterone helps to regulate electrolyte balance and works in conjunction with other hormones such as renin and angiotensin, forming a pivotal part of the renin-angiotensin-aldosterone system (RAAS) that is essential for maintaining cardiovascular stability under various physiological conditions.

In contrast, while insulin, adrenaline, and thyroxine are involved in other bodily functions—such as glucose metabolism, stress responses, and metabolic rate regulation, respectively—they do not primarily focus on blood pressure regulation in the same direct manner as aldosterone. This clear focus on sodium regulation and blood volume increase makes aldosterone the key hormone for blood pressure management.