Endothelin-1 in children with acute poststreptococcal glomerulonephritis and hypertension.

BACKGROUND

Endothelin-1 (ET-1), the most potent vasoconstrictor peptide, is known to play a role in arterial hypertension. In patients with acute poststreptococcal glomerulonephritis (APSGN) an increase in the production of ET-1 is suspected due to damaged endothelium, platelet activation and increased thrombin production in the glomeruli. The aim of the present study was to investigate whether the levels of plasma ET-1 are elevated in children with APSGN. Furthermore, we examined the association between plasma ET-1 levels and blood pressure levels in the same children.

METHODS

We studied 18 children (14 boys) with APSGN (mean age 7.44 to approximately 2.82 years). Fourteen healthy children served as controls. The following parameters were evaluated: plasma ET-1, plasma atrial natriuretic peptide (ANP), plasma renin (Rn), serum aldosterone (Aldo), creatinine clearance (Ccr) and fractional excretion of sodium (FENa).

RESULTS

The mean plasma ET-1 concentrations were higher in patients with APSGN (3.39 to approximately 1.86 pg/mL) compared to controls (1.40 to approximately 0.15 pg/mL; P=0.0001). Patients with APSGN also had higher plasma ANP concentrations (41.67 to approximately 27.99 pg/mL) than the controls (22.80 to approximately 4.24 pg/mL; P=0.011). Plasma Rn concentrations were lower in patients (24.54 to approximately 16.34 microU/mL) compared to controls (56.76 to approximately 32.36 microU/mL; P=0.027). A positive correlation was found between ET-1 plasma concentrations and the height of systolic or diastolic blood pressure (r=0.57, P=0.013 and r=0.53, P=0.023, respectively).

CONCLUSIONS

Our results suggest that increased plasma ET-1 concentrations may play an important role in the pathogenesis of hypertension in children with acute poststreptococcal glomerulonephritis.