Which of the following protein causes the dilation of blood vessels?
AHistamine
BPyrogens
CInterferon
DNone of these
Answer:
A. Histamine
Read Explanation:
Mast cells are large cells with densely granular cytoplasm that are found in connective tissues.
Mast cell granules contain mediators of inflammation, such as histamine, serotonin, and various chemotactic factors (substances that attract white blood cells to the area of infection).
Histamine released from ruptured mast cells causes marked dilation of all the arteries so that a large amount of fluid is passed from the blood to the tissues and there is a drastic fall in blood pressure.
