Interaction between bone morphogenetic proteins and endothelin-1 in human pulmonary artery smooth muscle.
Genetic mutations in bone morphogenetic protein receptor 2 (BMPR2) have been shown to occur in patients with familial and idiopathic pulmonary arterial hypertension (PAH). However the interactions between ligands for this receptor and other mediators implicated in heritable PAH have not been investigated. This study examines the regulation of endothelin-1 (ET-1), a potent vasoconstrictor and comitogen that is implicated in the pathogenesis of heritable PAH, by ligands for the BMPR2. Immunohistochemical studies showed that pulmonary artery segments removed from normotensive human lungs express BMPR2 and bone morphogenetic proteins 2, 4 and 7 (BMP2, BMP4 and BMP7). In the presence of BMP7 and BMP4 there was a significant inhibition of ET-1 release, induced by cytokines, from cultured pulmonary artery smooth muscle cells. Fresh ring segments of pulmonary artery were assessed for their response to ET-1 in the presence and absence of BMP2, BMP4 and BMP7. BMP7 inhibited contraction in response to ET-1 in a concentration-dependent manner. BMP2 and BMP4 had no significant effect on the response to ET-1. These results suggest that BMP7 has the ability to regulate the effects of endothelin-1 in the pulmonary circulation. Genetic mutations in BMPR2 may lead to a loss of these regulatory mechanisms and contribute to the pathogenesis of pulmonary hypertension.
Imperial College London, Heart Science Centre, Harefield Hospital, Harefield, Middlesex, UB9 6JH, United Kingdom.
Sarah
S
Din
Padmini
P
Sarathchandra
Magdi H
MH
Yacoub
Adrian H
AH
Chester
D000328:Adult; D000368:Aged; D055419:Bone Morphogenetic Protein 7 / Q000502:physiology; D052006:Bone Morphogenetic Protein Receptors, Type II / Q000502:physiology; D019485:Bone Morphogenetic Proteins / Q000032:analysis / Q000502:physiology*; D002478:Cells, Cultured; D019332:Endothelin-1 / Q000502:physiology*; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000209:etiology; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology*; D011651:Pulmonary Artery / Q000187:drug effects / Q000502:physiology*; D014661:Vasoconstriction / Q000187:drug effects
D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D019332:Endothelin-1; C498218:BMPR2 protein, human; D052006:Bone Morphogenetic Protein Receptors, Type II