A decrease in blood pressure / volume will not cause the release of :

Options

A. Renin
B. Atrial natriuretic factor
C. Aldosterone
D. ADH

Answer

To solve the question "A decrease in blood pressure/volume will not cause the release of:", we need to analyze the options provided and understand the physiological responses to a decrease in blood pressure or volume.

### Step-by-Step Solution:

1. **Understanding Blood Pressure and Volume Regulation**:
- The body has mechanisms to regulate blood pressure and blood volume. When there is a decrease in either, the body responds by releasing certain hormones to help restore normal levels.

2. **Analyzing Each Option**:
- **Option A: Renin**: Renin is released by the kidneys in response to low blood pressure or low blood volume. It helps in the formation of angiotensin, which increases blood pressure. Thus, renin would be released.

- **Option B: Atrial Natriuretic Factor (ANF)**: ANF is released by the heart when there is an increase in blood pressure or volume. It promotes the excretion of sodium and water, which decreases blood volume and pressure. Therefore, a decrease in blood pressure or volume will not cause the release of ANF.

- **Option C: Aldosterone**: Aldosterone is a hormone produced by the adrenal glands that promotes sodium retention and potassium excretion. It is released in response to low blood pressure or volume, so it would be released.

- **Option D: ADH (Antidiuretic Hormone)**: ADH is released from the posterior pituitary gland in response to low blood volume or high blood osmolarity. It helps in water retention, thus it would also be released.

3. **Conclusion**:
- Based on the analysis, the hormone that will not be released in response to a decrease in blood pressure or volume is **Atrial Natriuretic Factor (ANF)**.

### Final Answer:
**Option B: Atrial Natriuretic Factor (ANF)**

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