Beneficial effect of dehydroepiandrosterone on pulmonary hypertension in a rodent model of pulmonary hypertension in infants.

BACKGROUND: Pulmonary hypertension (PH) is a disease that affects the adult or infant population. Dehydroepiandrosterone (DHEA), a steroid hormone, has been previously shown to prevent and to reverse PH in an adult rat model. We thus investigated its effect in a rat-pup model of chronic hypoxic PH. METHODS: Animals were maintained for 3 wk in a hypobaric chamber to induce PH, with or without concomitant treatment with DHEA (30 mg/kg every alternate day). RESULTS: DHEA significantly reduced mean pulmonary artery pressure (measured by right cardiac catheterization), pulmonary artery remodeling (evaluated by histology), and right-ventricular hypertrophy (measured by echography and by the Fulton index). At the level of the pulmonary artery smooth muscle cell (PASMC), DHEA increased activity and expression of the large-conductance Ca2+-activated potassium channel (BKCa) (assessed by means of the patch clamp technique). DHEA also inhibited both serotonin- and KCl-induced contraction and smooth muscle cell proliferation. CONCLUSION: Collectively, these results indicate that DHEA prevents PH in infant rats and may therefore be clinically relevant for the management of PH in human infants.