of, relating to, or of the nature of preference: preferential policies. 2. showing or giving preference: a preferential hiring system. 3. receiving or enjoying preference, as a country in trade relations; favored. Origin of preferential.
Histamine dilates post-capillary venules, activates the endothelium, and increases blood vessel permeability. This leads to local edema (swelling), warmth, redness, and the attraction of other inflammatory cells to the site of release. It also depolarizes nerve endings (leading to itching or pain).
Mast Cells: Release histamine and heparin after an injury/infection, stimulating local inflammation. âª Lymphocytes: Develop into plasma cells to create antibodies to fight an infection. âª Microphages: Endocytotic drinking. âª Melanocytes: Store melanin, determining skin color. Protects DNA from sun damage.