Left/right difference in the course and division of the pulmonary arterial branches in the lung upper lobe: A study using human embryos and early fetuses. Issue 5 (24th July 2020)

• Record Type: Journal Article
• Authors: Jin, Zhe Wu; Hayashi, Shogo; Murakami, Gen; Wilting, Jörg; Rodríguez‐Vázquez, José Francisco; Abe, Shinichi
• Is Part Of: Journal of anatomy. Volume 237:Issue 5(2020)
• Page Start: 854
• Page End: 860
• Publication Date: 2020-07-24
• Subjects: bronchial tree -- human embryo and fetus -- left -- lung upper segmental arteries -- right difference -- topographical anatomy; Anatomy -- Periodicals; 571.3
• DOI: 10.1111/joa.13264
• Languages: English
• ISSNs: 0021-8782

Abstract

Abstract: Although left/right differences in a configuration of the pulmonary artery (PA) and its branches are well known, there is little information as to when and how such differences are established. Examination of serial sagittal sections of 25 embryos and fetuses at 6–7 weeks of gestation demonstrated that, at O'Rahilly stages 18–20, the right earliest first branch of PA originated in the anterior side of the upper lobar bronchus and overlay the upper bronchi, in contrast to the left branch which was located posteriorly and constricted medially by the upper posterior bronchus B1 + 2b. The right earliest branch was most likely to correspond to the future superior trunk, while the left branch might be a lingual artery. At stages 21–23, the upper posterior parenchyma was still underdeveloped in the left lung, since the ductus arteriosus and the left common cardinal vein seemed to make the left upper thoracic cavity narrow. Conversely, in the right lung, the thick S2 seemed to require a double arterial supply from both the superior and inferior arterial trunks. On the left, A3 originated at the lung apex and took a long descending course along the lung anterior surface. This high position of A3 might soon be corrected by an increased volume of S3. Overall, in contrast to the lower and middle lobes, early‐developed branches of the PA did not accompany upper segmental and subsegmental bronchi. A mechanism "differential growth" seemed to explain how to correct the fetal morphology to provide the adult morphology with variations. Abstract : This study describes observations of histological sections from serial sagittal sections of 25 embryos and fetuses at 6–7 weeks of gestation and demonstrating how left/right differences in a configuration of the pulmonary artery and its branches establishes.