In response to decrease in blood volume and blood pressure which of the following do not occur ?

Options

A. Secretion of renin
B. Secretion of aldosterone
C. Secretion of vassopressin
D. Secretion of ANF

Answer

To answer the question regarding which of the following does not occur in response to a decrease in blood volume and blood pressure, we can analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding the Situation**:
- When there is a decrease in blood volume and blood pressure, the body initiates compensatory mechanisms to restore normal levels.

2. **Analyzing Renin Secretion**:
- **Renin** is secreted by the juxtaglomerular cells of the kidneys in response to low blood pressure.
- It catalyzes the conversion of angiotensinogen to angiotensin I, which is then converted to angiotensin II, a potent vasoconstrictor that increases blood pressure.
- **Conclusion**: Renin secretion occurs.

3. **Analyzing Aldosterone Secretion**:
- **Aldosterone** is a hormone that promotes sodium reabsorption in the kidneys.
- Increased sodium reabsorption leads to water retention, which helps to increase blood volume and blood pressure.
- **Conclusion**: Aldosterone secretion occurs.

4. **Analyzing Vasopressin Secretion**:
- **Vasopressin** (also known as antidiuretic hormone, ADH) is released in response to low blood pressure and promotes water reabsorption in the kidneys.
- It also acts as a vasoconstrictor, which helps to increase blood pressure.
- **Conclusion**: Vasopressin secretion occurs.

5. **Analyzing Atrial Natriuretic Factor (ANF) Secretion**:
- **Atrial Natriuretic Factor (ANF)** is secreted by the atria of the heart in response to increased blood volume and pressure.
- ANF promotes the excretion of sodium and water by the kidneys, which decreases blood volume and pressure.
- In the case of decreased blood volume and pressure, ANF secretion would not occur as it would be counterproductive.
- **Conclusion**: ANF secretion does not occur.

### Final Answer:
The secretion of **Atrial Natriuretic Factor (ANF)** does not occur in response to a decrease in blood volume and blood pressure.

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