How does Angiotensin work in the body?

Angiotensin can specifically cause an increase in blood pressure and peripheral vascular resistance. It controls animal vascular smooth muscle receptors, causing vasoconstriction. Therefore, it is more effective in raising blood pressure than general sympathomimetic amines (such as norepinephrine, phenylephrine, metaraminol, hyperbaric allergy, etc.), and there is no serious tissue necrosis and no effect on renal function. side effect. This is an emergency medicine that raises blood pressure.

Under normal circumstances, due to the less secretion of renin, the level of angiotensin in the blood is low, and the regulation effect on blood pressure is not obvious. However, in the case of massive blood loss, due to the significant reduction in arterial blood pressure, renal blood flow decreases, and the production of angiotensin increases, which plays an important role in preventing excessive blood pressure drop and blood pressure rise.
In patients with chronic spasm or narrowing of renal vessels, increased angiotensin production due to decreased renal blood flow can lead to renohypertension. In addition, vasopressin can cause strong vasoconstriction, but it does not participate in blood pressure regulation under normal circumstances. When the circulating blood volume decreases due to blood loss, the concentration of the hormone in the blood will increase significantly, which plays a role in maintaining circulating blood volume, Maintain arterial blood pressure. Angiotensin is used in fainting and shock-induced hypotension from various causes, including anesthesia and substance overdose, and in cardiac surgery to maintain normotension.