RAASjärjestelmän

RAASjärjestelmän, which translates to the "RAAS system," refers to the Renin-Angiotensin-Aldosterone System. This is a critical hormonal cascade that plays a significant role in regulating blood pressure and fluid balance within the body. The system is initiated when the kidneys detect a drop in blood pressure or blood volume, or a decrease in sodium levels.

In response, the kidneys release an enzyme called renin. Renin then acts on angiotensinogen, a protein produced by the liver, to form angiotensin I. Angiotensin I is then converted by an enzyme primarily found in the lungs, angiotensin-converting enzyme (ACE), into angiotensin II.

Angiotensin II is a potent vasoconstrictor, meaning it narrows blood vessels, which directly increases blood pressure. It also stimulates the adrenal glands to release aldosterone. Aldosterone acts on the kidneys, promoting the reabsorption of sodium and water back into the bloodstream, which further increases blood volume and therefore blood pressure. The RAAS system also influences thirst, encouraging increased fluid intake.

Dysregulation of the RAAS system is implicated in various cardiovascular diseases, including hypertension (high blood pressure), heart failure, and kidney disease. Consequently, many medications used to treat these conditions target different parts of the RAAS pathway, such as ACE inhibitors and angiotensin II receptor blockers (ARBs), to lower blood pressure and reduce strain on the cardiovascular system.