Mast cells found in areolar tissue secrete

Options

A. serotonin
B. heparin
C. histamine
D. all of these

Answer

To answer the question "Mast cells found in areolar tissue secrete," we will analyze the options provided and determine which substances are secreted by mast cells.

### Step-by-Step Solution:

1. **Identify Mast Cells**:
- Mast cells are a type of connective tissue cell that are primarily found in areolar connective tissue. They play a crucial role in the immune response.

2. **Analyze the Options**:
- **Option 1: Serotonin**:
- Serotonin is a neurotransmitter that contributes to mood regulation. However, it is primarily produced in the brain and gut, not by mast cells.
- **Option 2: Heparin**:
- Heparin is an anticoagulant that prevents blood clotting. It is indeed secreted by mast cells.
- **Option 3: Histamine**:
- Histamine is an inflammatory mediator that is released by mast cells during allergic reactions and in response to foreign particles. It plays a significant role in the inflammatory response.
- **Option 4: All of these**:
- This option suggests that mast cells secrete serotonin, heparin, and histamine.

3. **Evaluate the Correct Answer**:
- Since mast cells secrete both heparin and histamine, but not serotonin, the correct answer cannot be "all of these." Therefore, the correct answer is that mast cells secrete heparin and histamine.

### Conclusion:
The correct answer to the question is **heparin and histamine**, but since the question asks for all substances that mast cells secrete, the most accurate answer based on the options provided is **heparin and histamine**.

### Final Answer:
Mast cells found in areolar tissue secrete **heparin and histamine**.

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