Natriuretic peptide system and endothelin in aneurysmal subarachnoid hemorrhage

Abstract
✓ The natriuretic peptide system consists of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). The system is implicated in the control of body fluid homeostasis, causes natriuresis and diuresis (ANP and BNP), and regulates vascular tone (CNP). A reciprocal relationship between ANP and endothelin (ET) has been suggested, and earlier studies have documented a possible role of ET in cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH). The authors studied plasma ANP, BNP, CNP, and ET for 6 consecutive days in 13 patients with SAH by using radioimmunoassay. The median admission values for ANP were 31.5 pg/ml (range 16.8–323 pg/ml [normal 15 ± 7 pg/ml]); for BNP, 45.3 pg/ml (range 2.2–80.2 pg/ml [normal 12 ± 9 pg/ml]); for CNP, 7.7 pg/ml (range < 2–20 pg/ml [normal 5.2 ± 3 pg/ml]); and for ET, 11 pg/ml (range 6.5–25.1 pg/ml [normal 7.2 ± 4 pg/ml]). Additional increases (defined as > 100% increase on two consecutive measurements) were noted in ...