Page 86 - Veterinary Immunology, 10th Edition

on nerve cells, smooth muscle cells, endothelial cells, neutrophils,
VetBooks.ir eosinophils, monocytes, dendritic cells, and T and B cells. When

histamine binds to these receptors, it stimulates endothelial cells to
produce nitric oxide, a potent vasodilator. At the same time, the

histamine causes blood vessel leakage, leading to fluid escape and
tissue edema. Histamine also upregulates TLR expression on
sentinel cells.

FIG. 3.6 Structure of some of the major vasoactive molecules
generated during acute inflammation.

Serotonin (5-hydroxytryptamine, 5-HT), a derivative of the amino
acid tryptophan, is another amine found in the mast cells of rodents

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