Arterial hypertension progression and changing activity of renin-angiotensin-aldosterone and sympatho-adrenal systems

Aim. To study the changing activity of renin-angiotensin-aldosterone system (RAAS) and sympatho-adrenal system (SAS) in progressing arterial hypertension (AH). Material and methods. The study included 480 AH patients with high cardiovascular risk, aged 18-65 years (mean age 52 +/- 12 years); 102 men and 378 women. The participants were randomized by the levels of Reberg-estimated glomerular filtration rate (GFR) and the results of radio-isotope renography (RRG) with 123 I-hippuran. Plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were assessed by the radio-immune method, and circadian excretion of adrenaline and noradrenaline (CAE. CNAE) by the fluorometric method. Results. In patients with GFR 115-135 ml/min, mean PAC was 0,53 0,06 nmol/l, in those with GFR 80-115 ml/min -0,76 +/- 0,08 nmol/l (43,4% increase; p<0,05), and in those with GFR <60 ml/min - 0,84 +/- 0,06 nmol/l (58,5% increase; p<0,01). The maximal increase in PRA (+47,6%; p<0,05), CAE (+36,6%; p<0,05), and CNAE (+92,4%; p<0,01) was observed in patients with chronic heart failure (CHF). Conclusion. At the early stages of renal dysfunction, noradrenaline synthesis was decreased. Progressing renal dysfunction, with increased secretion phase of RRG and GFR<80 ml/min, adrenaline and noradrenaline synthesis significantly increased, while PRA tended to increase. In Functional Class III CHD, SAS and RAAS activation were even more pronounced.