PATHOLOGY

Detailed explanation-1: -Inflammatory mediators are molecules produced by activated cells that intensify and prolong the inflammatory response. Histamine is a potent inflammatory mediator, commonly associated with allergic reactions, promoting vascular and tissue changes and possessing high chemoattractant activity.

Detailed explanation-2: -Histamine is released from cells in response to an antibody called immunoglobulin E (IgE). This antibody may be secreted in response to an invading pathogen such as a virus, bacteria, or an allergenic substance such as pollen. Histamine can also be released in response to injury caused by toxins.

Detailed explanation-3: -Histamine regulates antigen-specific Th1 and Th2 cells, as well as related antibody isotype responses. Histamine acting through its receptor (HR) type 2, positively interferes with the peripheral antigen tolerance induced by T regulatory (T(Reg)) cells in several pathways.

Detailed explanation-4: -Histamine is involved in the inflammatory response and has a central role as a mediator of itching. As part of an immune response to foreign pathogens, histamine is produced by basophils and by mast cells found in nearby connective tissues.

Detailed explanation-5: -Histamine works with nerves to produce itching. In food allergies it can cause vomiting and diarrhea. And it constricts muscles in the lungs, making it harder to breathe. Most worrisome is when histamine causes anaphylaxis, a severe reaction that is potentially fatal.