What is one of the effects caused by histamines?

Histamines play a crucial role in the body's immune response and are responsible for various physiological effects. One significant effect is capillary dilation, which occurs when histamines are released during allergic reactions or inflammatory processes. This dilation increases blood flow to the affected area, contributing to the classic symptoms of inflammation, such as redness and swelling.

The release of histamines leads to changes in the permeability of blood vessels, allowing fluid and immune cells to exit the bloodstream and enter tissues. This is essential for the body's response to allergens or pathogens, facilitating healing and defense mechanisms. Understanding the role of histamines in capillary dilation is important in grasping how the immune system operates and the treatments for allergic reactions, as antihistamines can block this effect, reducing symptoms.