Angiotensin II

Angiotensin II

Angiotensin II is the active form of A., which is an octapeptide formed from angiotensin I under the action of peptidase. Angiotensin II is one of the main hormones of the renin-angiotensin system and plays a key role in the regulation of blood pressure and water-salt balance.

Angiotensin II is formed in the body from the inactive decapeptide angiotensin I under the action of angiotensin-converting enzyme. Compared to angiotensin I, angiotensin II has much more pronounced biological activity.

The main effects of angiotensin II:

1. Constricts blood vessels, increasing blood pressure.

2. Stimulates the production of aldosterone in the adrenal cortex, which leads to sodium and water retention in the body.

3. Participates in the regulation of heart rate and myocardial contractility.

4. Stimulates the secretion of vasopressin and adrenocorticotropic hormone.

5. Activates the sympathetic nervous system.

Thus, angiotensin II plays a critical role in maintaining body homeostasis, regulating blood pressure and water-salt balance. Elevated levels of angiotensin II in the blood are associated with the development of hypertension, edema, and heart failure.

Angiotensin II: Role and functions in the body

Angiotensin II (AT II) is the active form of angiotensin, a biologically important octapeptide. It is formed from angiotensin I by the action of an enzyme known as peptidase. AT II plays a significant role in the regulation of various physiological processes in the human body.

One of the main functions of angiotensin II is its ability to constrict blood vessels. This process, called vasoconstriction, increases blood pressure. AT II also stimulates the release of aldosterone, a hormone that enhances the reabsorption of sodium and water in the kidneys. This leads to an increase in circulating blood volume and an additional increase in blood pressure.

Moreover, angiotensin II has a direct effect on various organs and tissues. It promotes hypertrophy of vascular smooth muscle, as well as cell proliferation and migration. As a result of this process, the formation of atherosclerotic plaques is possible, which is one of the main causes of cardiovascular diseases.

In addition, angiotensin II affects renal function. It increases the secretion of aldosterone and leads to constriction of the efferent arterioles of the renal glomeruli, which helps maintain glomerular filtration pressure and maintain renal perfusion. This is important for maintaining normal kidney function and fluid and electrolyte homeostasis in the body.

Angiotensin II also plays a role in the renin-angiotensin-aldosterone system. Renin, produced by kidney cells, stimulates the conversion of angiotensin I to angiotensin II. This system regulates the total volume of circulating blood and blood pressure.

It is important to note that imbalances in the renin-angiotensin-aldosterone system can be associated with various pathological conditions such as hypertension, heart failure and chronic kidney disease. Blockade of the action of angiotensin II can be used in the treatment of these diseases using angiotensin II receptor antagonists or angiotensin-converting enzyme inhibitors.

In conclusion, angiotensin II plays an important role in the regulation of blood pressure, kidney function, and fluid and electrite homeostasis in the body. Its ability to constrict blood vessels, stimulate the release of aldosterone, and have direct effects on various organs and tissues make it a key player in regulating hemodynamics and maintaining homeostasis.

Understanding the role of angiotensin II and its effect on the body helps to develop new approaches to the treatment of various cardiovascular diseases and kidney dysfunctions. Further research and development in this area may lead to the development of new pharmacological agents and therapeutic strategies aimed at more effectively regulating the renin-angiotensin-aldosterone system and improving patient health.

It is important to note that this article provides only general information about the role of angiotensin II in the body and is not a substitute for advice from a scientist or medical professional. For more detailed information on specific aspects of angiotensin II and its relationship to medical conditions, it is recommended that you consult relevant sources and conduct additional research.