reninangiotensinaldosteronsystemaktiviteten

Reninangiotensinaldosteronsystemaktiviteten, often abbreviated as RAAS activation, refers to the physiological cascade triggered by a decrease in blood pressure or reduced blood flow to the kidneys. This system plays a crucial role in regulating blood pressure and fluid balance within the body. The process begins when the kidneys, sensing low blood pressure, release an enzyme called renin. Renin then acts on angiotensinogen, a protein produced by the liver, to form angiotensin I. Angiotensin I is further converted to angiotensin II by an enzyme called angiotensin-converting enzyme (ACE), primarily found in the lungs. Angiotensin II is a potent vasoconstrictor, meaning it narrows blood vessels, thereby increasing blood pressure. Furthermore, angiotensin II stimulates the adrenal glands to release aldosterone. Aldosterone acts on the kidneys, promoting the reabsorption of sodium and water, which expands blood volume and also contributes to an increase in blood pressure. The RAAS is a vital mechanism for maintaining cardiovascular homeostasis, but its overactivation can contribute to conditions such as hypertension and heart failure.