However, the renin-angiotensin system also promotes protective, anti-inflammatory responses through its alternative renin-angiotensin pathway.
Renin by itself does not really affect blood pressure.
It is not able to alter the blood pressure as a precursor molecule.
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It must be transformed into the active form of angiotensin.
Angiotensin I
Angiotensin I also does not affect blood pressure much itself.
More specifically, it is called angiotensin-converting enzyme 1 (ACE1).
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This conversion can be blocked by drugs called ACE Inhibitors, an important throw in ofhigh blood pressure medication.
It has another important function as wellstimulating the release of aldosterone.
It regulates blood pressure by sending messages to the brain and the kidneys to help raise blood pressure.
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This thirst center is located in a part of the brain called thehypothalamus.
Drinking water, then, increases the fluid volume in the body and raises blood pressure.
Angiotensin II also stimulates the body’s “fight-or-flight response” to help increase blood pressure.
Renal effects
Thirst is not the only message from the brain in response to low blood pressure.
Angiotensin II also tells the hypothalamus to increase the production of a protein called antidiuretic hormone.
This hormone travels from the brain to the kidneys and tells the kidneys to reabsorb water from the urine.
Some people with hypertension have no identifiable cause.
This is referred to as primary, or essential, hypertension.
Other people have hypertension due to secondary causes.
Secondary hypertension can be triggered by hormonal imbalances in the classical RAS pathway.
It also has anti-inflammatory responses.
Because the classical and alternative RAA pathways oppose one another, they act to balance out their systemic effects.
The renin-angiotensin system plays an important role in the COVID-19 infectious disease process.
This recognition leads to a lock-and-key relationship that opens the door for the virus to enter.
It is preoccupied with facilitating viral entry into cells.
This leads to a reduction in anti-inflammatory responses and worsening of COVID-19 symptoms and infection.
The RAA inhibitors also indirectly affect the alternative RAA pathway and the infectious disease process of COVID-19.
It is important to speak with your medical provider about the risks and benefits of treatment with RAA inhibitors.
Frequently Asked Questions
Aldosterone is a hormone that helps the body manage water and sodium levels.
The RAA system has also been demonstrated to play a role in the infectious disease process of COVID-19.
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