Regulation of vascular tone and remodeling of the ductus arteriosus
スポンサーリンク
概要
- 論文の詳細を見る
The ductus arteriosus (DA), a fetal arterial connection between the main pulmonary artery and the descending aorta, normally closes immediately after birth. The DA is a normal and essential fetal structure. However, it becomes abnormal if it remains patent after birth. Closure of the DA occurs in two phases: functional closure of the lumen within the first hours after birth by smooth muscle constriction, and anatomic occlusion of the lumen over the next several days due to extensive neointimal thickening in human DA. There are several events that promote the DA constriction immediately after birth: (a) an increase in arterial oxygen tension, (b) a dramatic decline in circulating prostaglandinE2 (PGE2), (c) a decrease in blood pressure within the DA lumen, and (d) a decrease in the number of PGE2 receptors in the DA wall. Anatomical closure of the DA is associated with the formation of intimal thickening, which are characterized by (a) an area of subendothelial deposition of extracellular matrix, (b) the disassembly of the internal elastic lamina and loss of elastic fiber in the medial layer, and (c) migration into the subendothelial space of undifferentiated medial smooth muscle cells. In addition to the well-known vasodilatory role of PGE2, our findings uncovered the role of PGE2 in anatomical closure of the DA. Chronic PGE2-EP4-cyclic AMP (cAMP)-protein kinase A (PKA) signaling during gestation induces vascular remodeling of the DA to promote hyaluronan-mediated intimal thickening and structural closure of the vascular lumen. A novel target of cAMP, Epac, has an acute promoting effect on smooth muscle cell migration without hyaluronan production and thus intimal thickening in the DA. Both EP4-cAMP downstream targets, Epac and PKA, regulate vascular remodeling in the DA.
論文 | ランダム
- 八重山諸島黒島産膜翅目採集記録
- 税務論文 消費税法の改正と現行制度の再検討
- 解説 補償金債権が差し押さえられた場合の対応について
- 座談会 マンション敷地の取得(収用)について (特集 区分所有建物の取得)
- 犬の蕃殖阻止に就て