Secretion of aldosterone is under the control of

Options

A. Hypothalamic portal system
B. Hypothalamo-hypophyseal tract
C. RAAS pathway
D. Adrenal cortex

Answer

**Step-by-Step Solution:**

1. **Understanding Aldosterone**: Aldosterone is a hormone produced by the adrenal cortex, which is part of the adrenal glands located on top of the kidneys. Its primary function is to regulate sodium and potassium levels in the blood, which in turn helps control blood pressure.

2. **Identifying Control Mechanisms**: The secretion of aldosterone is regulated by various mechanisms, primarily the Renin-Angiotensin-Aldosterone System (RAAS). This system is crucial for maintaining blood pressure and fluid balance in the body.

3. **Explaining the RAAS Pathway**: The RAAS pathway begins when there is a decrease in blood pressure or blood volume. The kidneys detect this change and release an enzyme called renin. Renin converts angiotensinogen (produced by the liver) into angiotensin I, which is then converted into angiotensin II by the action of the enzyme ACE (Angiotensin-Converting Enzyme) primarily in the lungs.

4. **Role of Angiotensin II**: Angiotensin II has multiple effects, including stimulating the adrenal cortex to secrete aldosterone. This hormone then acts on the kidneys to promote sodium reabsorption and potassium excretion, leading to an increase in blood volume and blood pressure.

5. **Conclusion**: Therefore, while aldosterone is secreted by the adrenal cortex, its secretion is primarily controlled by the RAAS pathway.

**Final Answer**: The secretion of aldosterone is under the control of the RAAS pathway.

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