What is considered the pathogenesis of emphysema?
- proteolysis-antiproteolysis theory - imbalance between synthesis and breakdown of elastic tissue in alveolar walls
- oxidant-antioxidant imbalance
- = irritant (smoke) --> macrophages kill bacteria and foreign antigens by generating free radicals (oxidant-antioxidant theory)
- = creates pro-oxident environment with alveoli
- = damages alpha-1-antitrypsin protein (elastase inhibitor) so it cannot prevent uncontrolled breakdown of elastic tissue (by elastase)
Causes of emphysema
- pollutants in lungs
- hereditary deficiency of alpha-1-antitrypsin
Predominant cause of airway obstruction in asthma?
- Hypersensitivity response to some stimuli
- Associated with temporary obstruction
Key feature of asthma
Characteristic symptoms of asthma?
Main problem associated with asthma?
- Problem getting air in, then out, of lungs
3 features of Status Asthmaticus
- CO2 retention
- respiratory acidosis
What is the molecular basis for genetic defect in cystic fibrosis?
- In mucus-secreting epithelial cells, CFTR chloride channels not transported to plasma membrane
- Chloride ions NOT secreted into extracellular mucus
- Chloride plus sodium and water maintain viscosity of mucus