What substances do mast cells release during irritation?
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connective tissue
Randomly oriented collagenous fibers of varying size in a thin spread of loose areolar connective tissue (magnified about 370 Γ).
Mast cells are specialized cells of the immune system found throughout the body's connective tissues. When these cells are stimulated by irritation, injury, or allergens, they undergo a process called degranulation, during which they release various chemical mediators stored in their cytoplasmic granules.12
These released substances include:
- Histamine: A primary mediator that causes blood vessels to dilate and increase in permeability, facilitating the movement of immune cells to the site of injury.12
- Interleukins: Signaling proteins that help regulate immune responses.1
- Proteoglycans: Such as heparin, which plays a role in various biological processes.1
- Various enzymes: These contribute to the local inflammatory response.1
The release of these chemicals leads to characteristic symptoms of inflammation, such as swelling, increased mucus production, and the contraction of smooth muscles.12