lung biochemistry.txt

• 1) Submucosal glands (only in bronchi)
• 2) Goblet cells (only in bronchi) - Clara cells (after bronchi until alveoli)

Mucin (glycoprotein)

• 1) Sol: located around cilia to allow for easy movement. Less viscous.
• 2) Gel: located above cilia to catch particulate matter. More viscous.

Movement by sol and gel mucous to move sputum from distal to proximal so the matter can be removed through the mouth.

• CFTR
• It is activated by PKA and binds ATP. Once bound, it opens to allow chloride and water to flow through passively

• Dysfunctional CFTR transporter.
• Buildup of thick, viscous mucous.
• Traps particles and causes inflammation and infection.
• Leads to death.

• Dysfunctional cilia because of a breakdown of dynein in the microtubules of the cilia.
• The cilia can't move mucous around efficiently.
• People live longer than those with Cystic fibrosis.

Clara cells

• 1) Type I Alveolar: line epithelium
• 2) Type II Alveolar: secrete surfactant, lamellar bodies

• Antiprotease α-1antitrypsin
• binds to serine proteases to be removed and degraded. (SERPIN: serine protease inhibitor)

Maintains structural integrity of the alveoli so they do not collapse.

Polar heads repulse and hydrophobic tails clump together to keep the alveoli expanded.

Constituitive

• 1) form lamellar bodies
• 2) recycle surfactant products
• 3) immune response with macrophages

Insert phospholipids into surfactant monolayer

Formation of tubular myelin

No surfactant production so alveoli want to collapse.

>2

L/S ratio < 2

• 1) oxygen radicals
• 2) inflammation
• 3) tissue repair