Following are the hormones which do not produce secondary messenger except

Options

A. Cortisol
B. Aldosterone
C. Insulin
D. Oestrogen

Answer

To solve the question regarding which hormone produces a secondary messenger, we will analyze the hormones listed: cortisol, aldosterone, insulin, and estrogen.

### Step-by-Step Solution:

1. **Understanding Hormone Types**:
- Hormones can be classified based on their solubility and the location of their receptors.
- **Peptide hormones** (like insulin) are generally water-soluble and bind to receptors on the cell membrane.
- **Steroid hormones** (like cortisol, aldosterone, and estrogen) are lipid-soluble and typically bind to intracellular receptors.

2. **Identifying Secondary Messengers**:
- When a hormone binds to a membrane-bound receptor, it often activates a secondary messenger system. Common secondary messengers include cyclic AMP (cAMP), inositol trisphosphate (IP3), and calcium ions.
- Hormones that bind to intracellular receptors do not usually produce secondary messengers.

3. **Analyzing Each Hormone**:
- **Cortisol**: A steroid hormone that binds to intracellular receptors and does not produce secondary messengers.
- **Aldosterone**: Another steroid hormone that also binds to intracellular receptors and does not produce secondary messengers.
- **Insulin**: A peptide hormone that binds to membrane-bound receptors and activates secondary messenger pathways, specifically cAMP.
- **Estrogen**: A steroid hormone that binds to intracellular receptors and does not produce secondary messengers.

4. **Conclusion**:
- Among the hormones listed, **insulin** is the only hormone that produces a secondary messenger. The other three hormones (cortisol, aldosterone, and estrogen) do not produce secondary messengers.

### Final Answer:
The hormone that produces a secondary messenger among the given options is **insulin**.