Interrelationships among the renin-angiotensin system, sympathetic nervous system and atrial natriuretic peptide in...

Since it remains unclear how the regulatory mechanism of blood pressure and volume is associated with the renin-angiotensin system, the sympathetic nervous system, and atrial natriuretic peptide (ANP), we examined the changes in blood pressure and vasoactive hormones occurring in 12 patients with end-stage renal failure. They were divided into two groups, those who were anuric (group A, n = 7), and those who had a daily urine volume of more than 700 ml (group B, n = 5). The changes in the mean blood pressure (MBP) and these vasoactive hormones were observed during hemodialysis with water removal in group A and without water removal in group B, and during blood pressure reduction with sodium nitroprusside in group A. The basal levels of ANP in groups A and B were twice as high as those of normotensive subjects. During hemodialysis, MBP did not reveal any changes in both groups. In group A, ANP and body weight (BW) decreased, whereas the plasma renin activity (PRA) and norepinephrine (NE) increased. In group B, ANP remained stable during the first 3 hr and decreased at the end of hemodialysis. However, BW, PRA, and NE were unchanged. In group A, significant correlations were observed between the changes in BW and those in ANP (r = 0.52, p less than 0.05), PRA (r = -0.57, p less than 0.01), and NE (r = -0.76, p less than 0.01). During blood pressure reduction, MBP decreased with accompanying increases in NE and PRA. However, ANP did not show any change.(ABSTRACT TRUNCATED AT 250 WORDS)