CVR 21 biochem of lung

Question 1

What happens to elastase when you smoke?

Answer 1

ZAAT mutation activates it causing proteolysis leading to tissue damage and emphysema

Question 2

How do we treat patients with alpha 1 antitrypsin deficiency

Answer 2

Purified AAT before damage which restores anti neutrophil elastast activity and slow loss of function but has no effect on pulmonary gain.

Question 3

What does smoking do wot alpha 1 antitrypsin?

Answer 3

methionone 358 oxidises which effects the binding ability of elastase leading to emphysema

Question 4

How does gain of function mutations come about in alpha 1 anti

Answer 4

accumulation of ZAAT polymers in lumen

Question 5

What does a Z mutation do on alpha 1 anti?

Answer 5

Deficiency of AAT in lung polymerasation reaction between chains preventing it from being released from hepatocyte

Question 6

What does a S mutation do?

Answer 6

reduced Serpin activity

Question 7

What is a pIttsburg mutation?

Answer 7

Impairs AAT acting on serpin leading to clotting disorder

Question 8

What does alpha 1 antitrypsin disorders do?

Answer 8

Reduce AAT, increasing activity of elastase damaging alveoli causing hard breathing emphysema COPD and is progressive with liver cirrhosis.

Question 9

What does AAT do?

Answer 9

met 358 site reacts with elastase in suicide raction inhibitiion protease

Question 10

Interpleural pressure on inhalation

Answer 10

decreases.

Question 11

What is elastic recoil?

Answer 11

inversely related to lung compliance and is the rebound of lungs.

Question 12

What happens if elastase inreases

Answer 12

elastin decreases and elasticity decreases causing emphysema

Question 13

What is neonatal respiratory distress syndrome?

Answer 13

rapid breathing in newborn with sternal retraction. 1-2% newbornds with 20% contribution to neonate death. Correlates with suractant.

Question 14

What tests are used to assess suractant in amniotic fluid?

Answer 14

Lecithin sphingmyelin
phosphatidyglycerol
Surfactant/albumin ratio

Question 15

How do we treat NRDS

Answer 15

mother gets corticosteroids to increase enxymeatic activity of phosphatase and phosphatidic acidfor suracacnt synthesis.

Neonate gets exogenous surfactant immediately at birth

Oxygen

CPAP IV salts and sugar

Question 16

What is surfactant

Answer 16

Comes from type 2 alveolar cell. Develope into tubular myelin. Either degraded or recylced. Proteins that are linked to surface tension phosphilipid packaging and invovled in defence. Prevents collapse and increases compliance

Question 17

What are the four suractants assosiated proteins

Answer 17

SP-A SP -B SP-C SP-D

Question 18

How is a pulmonary surfactant formed

Answer 18

phoshatidycholine gains palmitate forming DPPC which joins apolipoproteins orming unique lipoprotein found only in lung

Question 19

Whats the strongest component of the surfactant

Answer 19

DPPC due to its apolar tail being less bent

Question 20

What does alveolar interdependence mean

Answer 20

each alveoli is surrounded by others and when one collapses the others stretch and distend to exert an expanding force on the collapsing one.

Question 21

What is compliance

Answer 21

ability of lungs and thorax to expand

Question 22

What is the hysteresis

Answer 22

air water surface tension occuring at the beginning of inflation

Question 23

What cell is responsible for gas exchange

Answer 23

Type 1 pneumocytes and is unable to replicate

Question 24

What do pulmonary endothelial cells produce

Answer 24

vasoactive peptides like TPA of ACE 1 and 2 inactivation of bradykinin which is a vasodilator.
Controls blood flow and pressure and viscisoty

Question 25

What do goblet cells do?

Answer 25

Secrete mucus. Present from bronchioles up in the epithelium. Increased in CF

Question 26

What do mast cells do?

Answer 26

Speed immune response. Rich in heparin and histamine. Asthma importance causing bronchoconstriction and mucus.

Question 27

What do lung macrophages do?

Answer 27

immune defence. phagocytosis cell turnover. Antimicrobiall. Antiviral.

Question 28

What do smooth muscle cells do?

Answer 28

control diameter and tension of bronchi. Produce cytokine IL5 and IL13

Question 29

What are large alveoloar and flat alveolar type

Answer 29

Large = Type 2 
Flat = Tyype 1

Question 30

Which is their more of cell types in alveloar

Answer 30

Type 1.

Type 2 is 5%