22–77 pg/mL; SI units: 22–77 ng/L
Lavender-top tube. Immediately send to lab on ice. Specimen
may need to be fasting; check with lab.
■ Secreted by atrial myocardium; exerts an antihypertensive
effect by increasing the renal excretion of sodium and water.
■ Secreted from the atria in response to atrial wall stretch.
■ Less useful than B-type natriuretic.
