What:

"Histamine is like a directional signal for white blood cells and makes it easier for them to reach pathogens by making capillaries more permeable. Too much histamine makes the capillaries too permeable, however. Although the red blood cells are too large to squeeze through the openings created, fluid will leak out under the skin, ultimately producing hives. "

Writer: Not Stated

LCC:

Where:

Date: Feb 21 2014 3:53 PM