Plasma Renin Activity

What it isAn enzyme released by specialized kidney cells when they sense low blood pressure or low sodium. It cleaves angiotensinogen to start the renin-angiotensin-aldosterone cascade.

DoesInitiates aldosterone release, vasoconstriction, and sodium retention.

GoodA mid-range renin alongside appropriate aldosterone signals balanced volume regulation.

BadSuppressed renin with high aldosterone signals primary aldosteronism. High renin signals dehydration, kidney artery stenosis, or appropriate response to drugs.