defense systems of the lung

Lectures on respiratory physiologyLectures on respiratory physiology

Defense Systems of the Defense Systems of the LungLung

Atmospheric Pollutants

Carbon monoxide

Sulfur oxides

Nitrogen oxides

Hydrocarbons

Particulates

Photochemical oxidants

Perfect Lung

Types and sources of pollutants

Photochemical Oxidants

hydrocarbons

nitrogen oxides

ozone, peroxyacyl nitrate,

aldehydes, acrolein, etc.

sunlight

Perfect Lung

Examples of smog

Effects of cigarette smokeCarbon monoxide causes up to 10% hemoglobin

“Tars” cause bronchial carcinoma

Smoking causes chronic bronchitis, emphysema,

bronchial carcinoma and coronary heart disease

Insidious effects of

tobacco advertising

Cancer death rates (male) from 1930 to 2004

Effect of single cigarette on airways

Behavior of Aerosols in the Lung

Deposition

Clearance

Perfect Lung

Mechanisms of deposition of aerosol

Perfect Lung

Sites of aerosol deposition

Perfect Lung

Mechanisms of deposition of aerosol

Accumulation of dust in a coal-miner’s lung

Perfect Lung

Mechanisms of deposition of aerosol

Clearance of Deposited Particles

Mucociliary system

Alveolar macrophages

Clearance of deposited particles

Mucociliary escalator

Airway wall showing a mucous gland

Normal airway (above); Enlarged mucous glands (below)

Goblet Cell

Mucociliary escalator

Gel layer of the mucus above the sol layer

Cilia just touching the gel layer

Ciliary action

Structure of microtubule; diagram (left), EM (right)

Impairment of Normal Mucociliary Function

Mucus: too much, or change in composition, e.g. chronic bronchitis, cystic fibrosis, asthma

Cilia: paralysis by toxic gases

bronchial epithelium destroyed

congenital defect of ciliary motion

Alveolar MacrophageAlveolar Macrophage

Alveolar macrophage in the corner of an alveolus

Impairment of Normal Macrophage Function

Inhaled gases such as ozone, cigarette smoke

Toxic particles such as silica

Alveolar hypoxia, radiation, corticosteroids, alcohol ingestion