They’re chemicals your immune system makes. Histamines act like bouncers at a club. They help your body get rid of something that’s bothering you — in this case, an allergy trigger, or “allergen.” Histamines start the process that hustles those allergens out of your body or off your skin.

What is the difference between histamine and serotonin?

There is a further difference between the response to serotonin shown in Fig. 2 and the response to histamine. Although both agents increase JvПA at the higher value of Pc to a similar extent, serotonin appears to reduce the intercept, уДр, more than histamine, whereas histamine increases Lp more than serotonin.

How does histamine affect the body?

Once released from its granules, histamine produces many varied effects within the body, including the contraction of smooth muscle tissues of the lungs, uterus, and stomach; the dilation of blood vessels, which increases permeability and lowers blood pressure; the stimulation of gastric acid secretion in the stomach; …