Low blood pressure or low salt in the blood causes glomerular cells to release renin, which leads to formation of angiotensin I, which after conversion to angiotensin II causes constriction of blood vessels leading to the glomeruli (reducing filtrate volume). Angiotensin II also causes aldosterone release. Aldosterone is a steroid hormone released by the adrenal cortex. Its primary function is to regulate salt reabsorption in the distal convoluted tubule (as well as the sweat glands, salivary glands, and colon).

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