What releases Aldosterone in order to increase blood pressure?

Aldosterone is a hormone produced and released by the adrenal cortex, which is the outer layer of the adrenal glands located atop the kidneys. The primary role of aldosterone is to regulate blood pressure and electrolytes by promoting sodium reabsorption and potassium excretion in the kidneys.

When blood pressure drops or sodium levels fall, the adrenal cortex responds by releasing aldosterone into the bloodstream. This mechanism is part of the renin-angiotensin-aldosterone system (RAAS), which is activated in response to low blood flow to the kidneys. Once aldosterone is released, it acts on the renal tubules to enhance sodium retention; this process leads to water retention, increasing blood volume and consequently raising blood pressure.

The other options do not synthesize or release aldosterone. The liver is involved in various metabolic processes, including synthesizing proteins and producing factors important for blood clotting, but it does not play a direct role in aldosterone production. The kidneys filter blood and manage fluid balance, but they do not secrete aldosterone. The posterior pituitary primarily releases hormones such as antidiuretic hormone (ADH) and oxytocin, neither of which is directly involved in the production of aldosterone. Therefore, the adrenal