| Three-dimensional serial section computer reconstruction of the arrangement of the structural components of the parabronchus of the Ostrich, Struthio camelus lung. | |
| | |
MedLine Citation:
|
PMID: 19768752 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
The Ostrich, Struthio camelus is the largest extant bird. The arrangement of the airway and the vascular components of the parabronchus of its lung were investigated by 3D serial section reconstruction. Modestly developed atrial muscles, shallow atria, paucity of infundibulae with preponderant origination of the air capillaries (ACs) from the atria and lack of interparabronchial septa, structural features that epitomize lungs of most highly derived metabolically active volant birds were observed. Intertwined very closely, the ACs and the blood capillaries (BCs) are not straight, blind-ended tubules that run in contact, counter and parallel to each other as has been claimed and/or modeled. Crosscurrent (perpendicular = orthogonal) orientation between the centripetal (inward) flow of the venous blood (VB) from the periphery of the parabronchus and the flow of air in the parabronchial lumen occur. Also, a countercurrent-like arrangement between the ACs which convey air centrifugally (outwards = radially) and the BCs that transport venous blood centripetally (inwards) was identified. The VB is conveyed to the parabronchus by the interparabronchial arteries and delivered to the exchange tissue by the intraparabronchial arterioles: it is then arterialized at the infinitely many points where the ACs and the BCs contact. Functionally, the crosscurrent arrangement grants a multicapillary serial arterialization arrangement which extends the time that the respiratory media, air and blood, are exposed to each other. The contribution that the countercurrent-like arrangement makes to the gas exchange process remains obscure. |
| | |
Authors:
|
John N Maina; Jeremy D Woodward |
Publication Detail:
|
Type: Comparative Study; Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: Anatomical record (Hoboken, N.J. : 2007) Volume: 292 ISSN: 1932-8494 ISO Abbreviation: Anat Rec (Hoboken) Publication Date: 2009 Nov |
Date Detail:
|
Created Date: 2009-11-05 Completed Date: 2010-02-01 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 101292775 Medline TA: Anat Rec (Hoboken) Country: United States |
Other Details:
|
Languages: eng Pagination: 1685-98 Citation Subset: IM |
Affiliation:
|
Department of Zoology, University of Johannesburg, Auckland Park, Johannesburg, South Africa. jmaina @uj.ac.za |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Adaptation, Physiological
/
physiology Animals Birds / anatomy & histology, physiology Bronchi / cytology*, physiology Capillaries / cytology, physiology Humans Image Processing, Computer-Assisted / methods Imaging, Three-Dimensional / methods Lung / cytology*, physiology Pulmonary Alveoli / cytology, physiology Pulmonary Artery / cytology, physiology Pulmonary Gas Exchange / physiology Respiratory Mucosa / cytology, physiology Respiratory Physiological Phenomena* Species Specificity Struthioniformes / anatomy & histology*, physiology |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Immunolocalization of G-Protein Alpha Subunits in the Olfactory System of the Cartilaginous Fish Scy...
Next Document: The Nature of Exocytosis in the Yolk Trophoblastic Layer of Silver Arowana (Osteoglossum bicirrhosum...