Exercise training counteracts the abnormal release of plasma endothelin-1 in normal subjects at risk for hypertension.

BACKGROUND: The hypothesis that in normotensive offspring of hypertensive parents exercise training could influence the systemic release of endothelin (ET)-1 during a provocative testing protocol was tested.
METHODS: The provocative handgrip test was performed in four groups of healthy young age-matched males: offspring of hypertensive parents following a regular swimming exercise regimen (group A, n = 14); offspring of hypertensive parents and leading a sedentary lifestyle (group B, n = 11); normal volunteers with no family history of hypertension: sedentary (group C, n = 10), and following a regular swimming regimen (group D, n = 10). The plasma ET-1 was measured at baseline, after 4 min of handgrip exercise at 50% maximal capacity and following 2 (R2) and 10 (R10) min of recovery from handgrip.
RESULTS: ET-1 plasma levels, within the normal range in all groups at baseline (group A 0.94 +/- 0.32 pg/ml, group B 0.84 +/- 0.26 pg/ml, group C 0.78 +/- 0.35 pg/ml, group D 0.85 +/- 0.26, p = NS) showed a progressive and significant increase in group B during and after handgrip exercise (peak handgrip 1.08 +/- 0.5 pg/ml, p = NS; R2 1.35 +/- 0.36 pg/ml, p < 0.05; R10 2.76 +/- 0.75 pg/ml, p < 0.01). Significant differences were found at R2 and R10 when the ET-1 levels measured in group B were compared to those observed in group A, group C and group D. Multivariate analysis demonstrated that the serum levels of ET-1 significantly contributed to predict handgrip-induced changes when the diastolic blood pressure was the dependent variable.
CONCLUSIONS: Routine aerobic exercise appeared to counteract the handgrip-induced abnormal release of plasma ET-1 and may favorably affect the preclinical endothelial alterations seen in healthy offspring of hypertensive parents.