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Where are mast cells found in the body?
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antihistamine
Antihistamines such as Benadryl (diphenhydramine) and Claritin (loratadine) can be purchased without prescriptions. Both of those agents act by blocking H1 receptors. However, whereas Benadryl binds to those receptors in the central nervous system (CNS), causing drowsiness, Claritin does not readily enter the CNS and thus does not normally cause drowsiness.
Mast cells are immune system cells found scattered throughout the connective tissues of the body. They are particularly concentrated in the following areas:
- Beneath the surface of the skin1
- Near blood vessels and lymphatic vessels1
- Within nerves1
- Throughout the respiratory system1
- Within the digestive and urinary tracts1
These cells play a central role in inflammatory and allergic responses by storing chemical mediators, such as histamine, in coarse granules. When stimulated by an allergen, mast cells undergo a process called degranulation, releasing these chemicals into the surrounding tissues.1