What is the term for the release of histamine-like chemicals that cause dilation of blood vessels?

The term that describes the release of histamine-like chemicals leading to the dilation of blood vessels is vasodilation. During this process, certain substances, such as histamine, are released in response to injury or inflammation, which causes smooth muscle relaxation in the walls of blood vessels. As a result, the diameter of the blood vessels increases, allowing more blood to flow through the affected area. This increased blood flow contributes to the classic signs of inflammation, including redness and warmth.

Vasoconstriction refers to the narrowing of blood vessels, which is the opposite of vasodilation and does not involve the release of histamine-like chemicals. Hyperemia is an increase in blood flow to a specific area, which can result from vasodilation but is not the term that directly describes the release of histamine itself. Neovascularization involves the formation of new blood vessels, which is a different process from simply dilating existing vessels due to the action of histamine or similar substances.