PCOL3011 Lecture Notes - Lecture 15: Asbestosis, Acute Respiratory Distress Syndrome, Macrophage
Document Summary
In contact with external environment: samples a large volume of air, >10,000 l per day, exposed to blood direct from right ventricle, has defence system (but can be overwhelmed) Categories of effects of inhaled toxicants: local effects, nasal, upper airways: larynx/trachea, lower airways & alveoli, distant effects, toxin absorbed into the body, toxic effects on distant organs , e. g. carbon monoxide (co, benzene. Paraquat, several cancer drugs (bleomycin, methotrexate, many others) Nasal function: air-conditioner of inhaled air, heats air, humidifies air, filter, captures large particles, captures water soluble gases. Nasal epithelium has cytochrome p450s - 1a1, 2b1, 4b1 in several species. Type 1 pneumocytes: line the airspaces thin cytoplasm - gas exchange. Type ii pneumocytes: located in corner of alveoli - produce surfactant - reduces surface tension so that alveoli remain open . Transform into type 1 cells if necessary - e. g. if type 1 cells are damaged. Where does it come from : goblet cells, mucous glands.
