[Atrial natriuretic factor and the lung].
Atrial natriuretic factor (ANF) is a peptide secreted by auricular cardiac cells and acts on the brain; it is a diuretic, a natriuretic and a vasodilator and inhibits the renin angiotensin aldosterone system at several levels. The lungs are rich in specific ANF receptors present both at a vascular cellular level and in the mesothelial cells. These receptors participate in the extraction of ANF during its pulmonary intravascular transit and also in its enzymatic degradation. Endogenous ANF (and exogenous) is a vasodilator of the pulmonary arterial bed, representing a regulatory system for right ventricular afterload and probably modifying pulmonary capillary permeability. Hypoxia and hypercapnia contribute by direct and indirect mechanisms to the stimulation of ANF secretion explaining their elevated levels in pulmonary arterial hypertension and chronic respiratory insufficiency. The lung can under certain conditions synthesise ANF itself as can neuro-endocrine bronchial tumours. ANF may be involved in the understanding of sodium retention during ventilation with PEEP and in the paraneoplastic hyponatraemia of certain bronchial tumours. Finally acute bronchial obstruction leads to hypersecretion of ANF which has some bronchodilator properties.
Ménard
O
O
Service de Pneumologie A, Hôpital Villemin, Nancy.
D009320:Atrial Natriuretic Factor / Q000502:physiology*; D006801:Humans; D008168:Lung / Q000502:physiology*; D008171:Lung Diseases / Q000503:physiopathology; D011652:Pulmonary Circulation / Q000502:physiology
D009320:Atrial Natriuretic Factor
Facteur atrial natriurétique et poumon.