4.4 Regulation of Bronchial Smooth Muscle

  1. What is asthma?
    Bronchospasm, mucous secretion, edema, and ASM remodeling
  2. What is airway smooth muscle (ASM) doing normally and in asthma?
    • Normal - not really doing much
    • Asthma - bronchospasm
  3. How is the bronchial tree innervated?
    • ASM - Parasympathetic (Cholinergic and Non-adrenergic non-cholinergic) 
    • Epithelium - Parasympathetic and Sympathetic
    • Mucosa - Sensory nerves
  4. Describe excitation-contraction coupling of ASM
    Relaxation is mediated via the opening of K+ channels (VIP) or activation of myosin light chain phosphatase (MI.P) (via NO and cGMP/PKG)
  5. What are the 3 endogenous compounds that can elicit contraction of the airway smooth muscle?
    • Histamine
    • Leukotrienes
    • Acetlycholine
  6. Compare and contrast different explanations for the molecular basis of asthma (immune mediated vs. nerve dysfunction)
    Immune - excessive inflammation that triggers histamine release
  7. What is the significance of the molecular qualities of ASM and its remodeling to the pathogenesis of asthma?
  8. Describe pharmacologic interventions for asthma and their rationale
    • B-agonists - promote bronchodilation
    • Phosphodiesterase inhibitors
    • Anticholinergics
    • Combination therapy is standard
Card Set
4.4 Regulation of Bronchial Smooth Muscle