Distribution of airway narrowing responses across generations and at branching points, assessed in vitro by anatomical optical coherence tomography
MetadataShow full item record
Background: Previous histological and imaging studies have shown the presence of variability in the degree of bronchoconstriction of airways sampled at different locations in the lung (i.e., heterogeneity). Heterogeneity can occur at different airway generations and at branching points in the bronchial tree. Whilst heterogeneity has been detected by previous experimental approaches, its spatial relationship either within or between airways is unknown.Methods: In this study, distribution of airway narrowing responses across a portion of the porcine bronchial tree was determined in vitro. The portion comprised contiguous airways spanning bronchial generations (#3-11), including the associated side branches. We used a recent optical imaging technique, anatomical optical coherence tomography, to image the bronchial tree in three dimensions. Bronchoconstriction was produced by carbachol administered to either the adventitial or luminal surface of the airway. Luminal cross sectional area was measured before and at different time points after constriction to carbachol and airway narrowing calculated from the percent decrease in luminal cross sectional area.Results: When administered to the adventitial surface, the degree of airway narrowing was progressively increased from proximal to distal generations (r = 0.80 to 0.98, P < 0.05 to 0.001). This 'serial heterogeneity' was also apparent when carbachol was administered via the lumen, though it was less pronounced. In contrast, airway narrowing was not different at side branches, and was uniform both in the parent and daughter airways.Conclusions: Our findings demonstrate that the bronchial tree expresses intrinsic serial heterogeneity, such that narrowing increases from proximal to distal airways, a relationship that is influenced by the route of drug administration but not by structural variations accompanying branching sites. © 2010 Noble et al; licensee BioMed Central Ltd.
Showing items related by title, author, creator and subject.
Elastic properties of the central airways in obstructive lung diseases measured using anatomical optical coherence tomographyWilliamson, J.; McLaughlin, R.; Noffsinger, W.; James, A.; Baker, V.; Curatolo, A.; Armstrong, J.; Regli, A.; Shepherd, K.; Marks, G.; Sampson, D.; Hillman, D.; Eastwood, Peter (2011)Rationale: Our understanding of how airway remodeling affects regional airway elastic properties is limited due to technical difficulties in quantitatively measuring dynamic, in vivo airway dimensions. Such knowledge could ...
Haemodynamic evaluation of coronary artery plaques : prediction of coronary atherosclerosis and disease progressionChaichana, Thanapong (2012)Coronary artery disease is the leading cause of death in advanced countries. Coronary artery disease tends to develop at locations where disturbed flow patterns occur, such as the left coronary artery. Haemodynamic change ...
Does smooth muscle in an intact airway undergo length adaptation during a sustained change in transmural pressure?Ansell, T.; McFawn, P.; McLaughlin, R.; Sampson, D.; Eastwood, Peter; Hillman, D.; Mitchell, H.; Noble, P. (2015)In isolated airway smooth muscle (ASM) strips, an increase or decrease in ASM length away from its current optimum length causes an immediate reduction in force production followed by a gradual time-dependent recovery in ...