Evidence for Presynaptic Alpha and Beta Adrenoceptors in the Human Pulmonary Artery: Characterization and Possible Functional Role

While certain etiologic factors causing pulmonary hypertension are well known, the pathogenesis of obstructive pulmonary vascular disease is not yet completely understood. Laboratory data suggest that pulmonary artery pressure and vascular resistance can be increased by activation of the sympathetic nervous system via release of noradrenaline (NA) from sympathetic nerve fibers in the blood vessel wall [1]. The sympathetic nervous system may also be involved in the development of pulmonary hypertension in children with congenital heart disease. Presynaptic adrenoceptors modulating NA release have been shown in various tissues of different species [4]. Therefore, we investigated whether such regulatory mechanisms for the release of NA also exist in the human pulmonary artery.