During inflammation, which of the following is secreted by connective tissue?

Options

A. serotonin
B. heparin
C. glucagon
D. histamine

Answer

To answer the question "During inflammation, which of the following is secreted by connective tissue?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Context of Inflammation**:
- Inflammation is a biological response to harmful stimuli, such as pathogens, damaged cells, or irritants. It involves various immune cells and signaling molecules.

2. **Recognize the Role of Connective Tissue**:
- Connective tissue plays a crucial role in the inflammatory response. It contains various cells, including mast cells, which are essential for mediating inflammation.

3. **Understand the Function of Mast Cells**:
- Mast cells are a type of immune cell found in connective tissue, particularly in areolar tissue. They contain large granules filled with various chemical mediators.

4. **Identify the Mediators Released by Mast Cells**:
- When activated during inflammation, mast cells release several substances, including histamine and serotonin. Histamine is particularly important in the inflammatory response.

5. **Evaluate the Options Given**:
- The options provided are:
1. Serotonin
2. Heparin
3. Glucagon
4. Histamine
- We need to determine which of these is primarily secreted by connective tissue during inflammation.

6. **Analyze Each Option**:
- **Serotonin**: While it is released by some cells, it is not the primary mediator of inflammation from mast cells.
- **Heparin**: This is an anticoagulant found in the blood and does not play a direct role in inflammation.
- **Glucagon**: This hormone regulates blood glucose levels and is not involved in the inflammatory process.
- **Histamine**: This is the main mediator released by mast cells during inflammation, causing symptoms such as redness, swelling, and itching.

7. **Conclude the Correct Answer**:
- Based on the analysis, the correct answer to the question is **Histamine**.

### Final Answer:
**Histamine** is secreted by connective tissue during inflammation.

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