Cellular bronchiolitis

Figure 3.10 The structure of the mammalian respiratory system (A) trachea, (B) bronchiole, (C) alveolar sac with blood supply, (D) arrangement of blood vessels around alveoli, (E) arrangement of cells and airspaces in alveoli showing the large surface area available for absorption, (F) cellular structure of alveolus showing the close association between (G) the endothelial cell of the capillary (H) with erythrocytes and (I) the epithelial cell of the alveolar sac. The luminal side of the epithelial cell is bathed in fluid, which also facilitates absorption and gaseous exchange. Source From Ref. 1.

Beta-2 Bronchiole smooth muscle Some arterioles (skeletal muscle, liver] Gastrointestinal smooth muscle Skeletal muscle and liver cells Uterus Gallbladder Relaxation (bronchodilation] Vasodilation Decreased motility Increased cellular metabolism Relaxation Relaxation... 

Phosgene has a relatively low solubility in water and consequently is able to penetrate to the terminal bronchioles and alveoli where it reacts chemically with cellular and... 

Fig. 3. The branching of the peripheral respiratory airways from bronchus to bronchiole to acinus. (The inset is a cross-section describing the cellular organization within a typical bronchus.)...

Cellular Components of the Bronchi, Bronchioles, Alveoli, and Pulmonary Vasculature... 

The toxicity of NO2 is often studied since it is a major component of air pollution however, a safe level is difficult to determine. A confounding effect is a certain tolerance to later NO exposure after a preliminary low-level exposure for a brief time (Mustafa and Tierney, 1978). NO2 levels of less than 0.5 ppm have been reported to enhance human airway hyperreactivity (Bylin et al., 1988). Toxic pulmonary effects of breathing NO2 at or below 5 ppm have been reported. These include altered surfactant chemistry and metabolism (Muller et al., 1994), epithelial hyperplasia of the terminal bronchioles, and increased cellularity of the alveoli in rats (Evans et al.,... 

Mice exposed continuously to an unspecified concentration of chlordane for 14-25 days had slight lung congestion and proliferation of bronchiole lining cells (Ingle 1953). In a series of experiments, rats exposed to 413 mg technical chlordane/m for 3 days had epithelial degeneration and cellular debris in the bronchii and alveoli (Khasawinah et al. 1989 Velsicol Chemical Co. 1984). Respiratory tract lesions were not observed in rats intermittently exposed to technical chlordane at <28.2 mg/m 8 hours/day, 5 days/week for 28 days or similarly to 10 mg/m for 90 days. Abnormal respiratory... 

In specific-pathogen-free, female BALB/c mice sensitised with picryl chloride, cellular infiltrates appeared around the bronchiole and its accompanying blood vessel at 12 h after an intratracheal instillation of picryl sulfonic acid and progressively expanded by 48 h (Nishida et al. 1999). As quantitated by computer-assisted morphometry, I-A dendritic cells and CD" Th cells significantly increased in number around the bronchiole to a maximum at 24 h, whereas F4/80 macrophages were... 

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