kinin

blood component

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Last updated

June 30, 2026

Quick Summary

Kinin refers to polypeptide hormones that are produced locally within tissues. These substances play a role in physiological processes by causing blood vessels to dilate and smooth muscles to contract.1

A notable example is bradykinin, a specific type of kinin. Bradykinin is formed in injured tissues and contributes to vasodilation in small arterioles. It is also believed to be involved in inflammatory responses and is composed of a chain of nine amino acid residues.2

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hormone
Endocrine-like glands and secretions
Blood contains kinins, which are polypeptides that originate in the blood and perhaps elsewhere; bradykinin, for example, causes contraction of most smooth muscles and has a very potent action in dilating certain blood vessels. Its function, which is not yet established, may be to regulate the rate…
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Blood contains kinins, which are polypeptides that originate in the blood and perhaps elsewhere; bradykinin, for example, causes contraction of most smooth muscles and has a very potent action in dilating certain blood vessels. Its function, which is not yet established, may be to regulate the rate…
Read More

inflammation
Chemical mediators of inflammation
systems of proteins—complement, the kinins, coagulation factors, and the fibrinolytic system—that generate various mediators of inflammation. Activated complement proteins serve as chemotactic factors for neutrophils, increase vascular permeability, and stimulate the release of histamine from mast cells. They also adhere to the surface of bacteria, making them easier targets…
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systems of proteins—complement, the kinins, coagulation factors, and the fibrinolytic system—that generate various mediators of inflammation. Activated complement proteins serve as chemotactic factors for neutrophils, increase vascular permeability, and stimulate the release of histamine from mast cells. They also adhere to the surface of bacteria, making them easier targets…
Read More