Which one of the following does not act as a neurotransmitter ?

Options

A. Acetylcholine
B. Epinephrine
C. Nor epinephrine
D. Cortisone

Answer

**Step-by-Step Solution:**

1. **Understanding Neurotransmitters**: Neurotransmitters are chemical substances that transmit signals across a synapse from one neuron to another. They are crucial for communication within the nervous system.

2. **Identifying Examples of Neurotransmitters**: Common examples of neurotransmitters include:
- Acetylcholine (ACh)
- Epinephrine
- Norepinephrine

3. **Analyzing the Options**: The question provides four options:
- Acetylcholine
- Epinephrine
- Norepinephrine
- Cortisone

4. **Determining Which is Not a Neurotransmitter**:
- Acetylcholine: This is a well-known neurotransmitter involved in muscle activation and other functions.
- Epinephrine: This is also a neurotransmitter, often associated with the fight-or-flight response.
- Norepinephrine: This functions as a neurotransmitter as well, playing a role in attention and responding actions.
- Cortisone: This is not a neurotransmitter; it is a hormone produced by the adrenal gland that helps regulate metabolism and immune response.

5. **Conclusion**: Based on the analysis, cortisone is the only option that does not act as a neurotransmitter.

**Final Answer**: Cortisone does not act as a neurotransmitter.

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