Angiotensin-II will perform all the following except

Options

A. Vasoconstriction
B. Hypernatremia
C. Increasing GFR
D. Excretion of `Na^(+)` in urine

Answer

To solve the question regarding the functions of Angiotensin-II, we need to analyze each of the provided options and determine which one is not a function of Angiotensin-II.

### Step-by-Step Solution:

1. **Understanding Angiotensin-II**: Angiotensin-II is a peptide hormone that plays a crucial role in regulating blood pressure and fluid balance. It is known for several physiological effects.

2. **Evaluating the Options**:
- **Option 1: Vasoconstriction**: Angiotensin-II is a powerful vasoconstrictor. It narrows blood vessels, which increases blood pressure. This option is true.
- **Option 2: Hypernatremia**: Angiotensin-II promotes the reabsorption of sodium ions in the kidneys, which can lead to an increase in sodium concentration in the blood (hypernatremia). This option is also true.
- **Option 3: Increasing GFR (Glomerular Filtration Rate)**: Angiotensin-II can increase GFR by constricting the efferent arterioles of the glomeruli, leading to increased pressure in the glomeruli. This option is true as well.
- **Option 4: Excretion of sodium ions in urine**: This option states that Angiotensin-II causes the excretion of sodium ions in urine. However, Angiotensin-II actually promotes sodium reabsorption, which means it reduces sodium excretion. Therefore, this option is false.

3. **Conclusion**: The correct answer is the option that states "excretion of sodium ions in urine," as this is not a function of Angiotensin-II.

### Final Answer:
Angiotensin-II will perform all the following except **excretion of sodium ions in urine**.

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