Background Endothelin is the strongest endogenic substance causing vasoconstriction.
Materials and methods The aim of the study was an assessment of the influence of a given angiotensin converting enzyme inhibitor therapy on blood pressure and endothelin-1 concentration in young population with mild to moderate hypertension.
There were 2 steps of this study. Into the first step (6 weeks) 19 young patients (14 men and 5 women) aged 16-19 were enrolled. The average age of this population was 17.6 ± 1.4 years. The patients were untreated or there was a 7 days wash-out period. Before enrolling and after 6 weeks of trandolapril therapy (2 mg/day) blood pressure and plasma endothelin-1 concentration were measured. Endothelin was measured by radioimmunoassay. In the second step of the trial blood pressure and endothelin-1 were assessed after 6 months of trandolapril therapy (2 mg/day).
Results In analysed group after 6 weeks of trandolapril therapy there was a significant both systolic and diastolic blood pressure lowering. The average systolic blood pressure values were reduced from 142.6 ± 9.7 mm Hg to 129.3 ± 8.4 mm Hg (p < 0.0003), the average diastolic blood pressure were reduced from 85.7 ± 6.9 mm Hg to 79.8 ± 8.6 mm Hg (p < 0.01). The average endothelin-1 concentration was: before therapy 9.33 ± 1.9 fmol/ml, after therapy 8.96 ± 2.2 fmol/ml (this lowering was not statistically significant). After 6 months of treatment the blood pressure reduction was on the same level, but there was a significant reduction of endothelin-1 plasma concentration (initial concentration - 9.33 ± 1.9 fmol/ml, final concentration - 7.49 ± 2.7 fmol/ml, p < 0.05).
Conclusion Trandolapril therapy, both short-time (6 weeks) and long-time (6 months) gave a significant blood pressure reduction, whereas only a long-time treatment caused a significant plasma endothelin-1 concentration reduction. The therapy did not influence on lipid.