In a previous study, an effective in vitro system was developed to understand how single cells suspended in CSF adhere to catheters and contribute to obstruction [ 14].
Elevation of PEL implied a spread of CMPI toward the luminal surface, and further investigation suggested that the activation of SPFs, which normally reside in the subperitoneal outer area of the colonic wall, contributes to obstruction of the bowel.
For a given cell, the MCD may then describe a criterion that determines whether IRBCs may be physically segregated and trapped by the spleen, or contribute to obstruction of capillaries in the microcirculation.
In COPD, remodeling of the small airways and lung parenchyma contributes to obstructions in air flow (Sköld 2010), whereas in asthma, airway obstruction may originate predominantly in the larger airways.
Although TGF- β1 is undoubtedly contributed to obstruction-induced fibrosis, it is normally secreted as a latent procytokine complex that needs activation before signaling through TGF- β receptor and mediating fibrogenic effects [ 18, 20].
IL-13 induces multiple features of allergic lung disease, including metaplasia and mucus hypersecretion, contributing to airway obstruction [ 36].
In addition, endothelial cell injury might induce a procoagulative response, leading to microthrombosis and contributing to vascular obstruction and hypoperfusion of multiple tissues [ 20].
The impairment of the distal airways is recognized as an important factor contributing to airflow obstruction [ 23], particularly in patients with severe asthma and nocturnal asthma [ 7].
EDN1 may act as a paracrine hormone causing sustained contraction of airway smooth muscle cells [ 13, 14], accelerated growth of both fibroblasts and airway smooth muscle cells [ 15, 16] and increased oedema formation and mucus secretion [ 8], contributing to airway obstruction.
Numerous studies have demonstrated the role of EDNR1 on bronchial smooth muscle contraction (via intracellular calcium input and modulation of acetylcholine or relaxant substances such as prostanoids or nitric oxide secretion), but also on mucus secretion, airway remodelling and inflammation, all features contributing to airway obstruction in asthmatics and smokers [ 35].
