Chapter 14. Respiratory System
Higher category: 【Biology】 Biology Index
7. Lung disease
1. Overview of Breathing
⑴ Stage of breathing
① Exhalation: Gas exchange between the atmosphere and the respiratory tract (ventilation)
② Diffusion: Gas exchange between respiratory tract and blood
③ Mass transport: Carrying of blood
④ Breathing: Gas exchange between blood and tissue cells
⑤ (Note) cell respiration: Receives O2 to oxidize organic matter and produces CO2 and ATP
⑵ Insect breathing: Direct air to the engine only
① Air flow: Institutions → Institutions → Air capillaries
○ 1st. Atmospheric O2 flows into the trachea (the thickest air duct) through the gate on the side of the abdomen
○ 2nd. Air entering the trachea is the trachea (a.K.a bronchiole)
○ 3rd. Air pockets exist due to the presence of expanded sites near tissues with high oxygen demand
○ 4th. O2 in the bronchus moves through the diffusion into the air capillary
② The shape of the organ is retained by the ring-shaped chitin
③ The end of the bronchus is filled with a dark blue liquid. → As the momentum increases, oxygen consumption increases, and most of this liquid is absorbed into the body fluid, which increases the volume of the bronchial tube containing air.
④ Diving Insect: Using Bubbles to Absorb Oxygen
⑶ Fish breathing: Using gills as a respiratory tract
① Located on both sides of the fish
② Four gill bows located between the mouth and the gill lids
③ Hundreds of gill filaments, lamellar up and down
○ Lamella: Practical gas exchange surface
④ Blood vessels passing through the gill: Afferent vessels, centrifugal vessels
○ Afferent blood vessels: Carries blood to the gills
○ Efferent vessels: Withdrawing blood from gills
⑤ Increased gas exchange efficiency by ventilation and backflow exchange
○ Backflow Exchange: Blood flow inside the lamellae and water flow in opposite directions
⑷ Amphibian breathing
① Using gills during larval period, then lungs when adult
○ Reptiles, birds and mammals breathe using their lungs
② Ventilate with positive pressure breathing
○ Breathe positively: Breathing, swallowing air, increasing the pressure near the breathing surface to allow oxygen in the air to dissolve in capillaries across the breathing surface
○ Breathing negative pressure. mammalia): A breath that lowers the pressure near the breathing surface so that oxygen in the air dissolves in capillaries that cross the breathing surface.
③ Skin respiration: 50% of gas exchanges through the skin
⑸ Bird breathing
① Envelope: Lungs and space inside some bones
② flow of air: Trachea → Bronchus → Lateral Bronchus → Air Capillary, two inhales and exhalations
○ Back air bag → Lung → Front air bag
○ 1st. First breath: Air fills the rear pockets
○ 2nd. First exhalation: The back airbag contracts and sends air to the lungs
○ 3rd. Second inhale: Air flows out of the lungs into the front airbag
○ 4th. Second exhalation: The anterior lung contracts and releases the air that entered the body by the first inhale
③ Advantages of bird breathing
○ Algae lungs are not blocked at the end → residual amount × → gas exchange efficiency ↑
○ Less contraction and relaxation than mammals
⑹ Mammal Breathing (See. 2, 3)
2. Lung Structure (Mammals)
⑴ Air flow: Mouth or nose → nasal cavity → pharynx → larynx → airway → bronchus → tracheobronchial (bronchial) → alveoli
① Air is filtered, warmed and humidified through the nasal passages
② Air from the nasal passages moves to the pharynx (inlet of the esophagus and larynx), where it meets food from the mouth.
③ Palate reflection
○ When swallowing food
○ Epiglottis: Structures that send food to the esophagus and air to the airways
○ 1st. The larynx moves up to close the epiglottis at the gate that corresponds to the entrance to the prayer
○ 2nd. Food goes down the esophagus and reaches over
○ Rest time: Prayer can open and breathe
○ Sends foreign substances trapped in the mucus of goblet cell to esophagus
④ vocal cords
○ The larynx and the lining of the airways (the role of the vocal cords) are fortified with cartilage to ensure airways at all times
○ High tone when strong contraction of vocal cord muscles, low tone when weak contraction
⑤ Bronchus: 2, the inner wall epithelial cells of the main bronchus pass the foreign body to the esophagus using cilia and mucus
⑵ Anatomy of the lungs
① The lungs are made of light spongy tissue, mostly filled with air-filled spaces
② Each lung is surrounded by a pleural sac that prevents gas exchange with the chest cavity
⑶ Alveoli
① 400 million, monolayer epithelium, diameter 0.1 to 0.3 mm
② Alveoli-capillary spacing: 0.1 to 1.5 μm for very smooth diffusion
③ Special structure of alveoli causes lung elasticity
○ The alveoli are muscleless (disrupting gas exchange) but the connective tissue contains large amounts of elastin, which allows it to contract and relax
○ Elastin fibers: Has elastic force opposite to tension
○ Moisture tension: Microscopic layers of moisture on alveoli attract each other to create strong contractile pressure
④ Types of Alveolar Cells
○ First alveolar cell: Mostly epithelial cells
○ Second alveolar cell: Secretion of surfactant on the surface of villi → Alveolar distortion due to surface tension of water

○ Smaller alveolar second alveolar cells secrete more surfactant to lower higher surface tension
○ Neonatal Respiratory Disorder Syndrome (NRDS): Lack of surfactant secretion due to premature death of infants, second stage alveolar cells
○ Macrophage: Foreign object removal
⑤ Number of alveoli 8 × 106 → Respiratory epithelium area 50 ~ 100 m2 (See. Body surface area ~ 2 m2)
⑷ Functional structure of the lungs
① Lung blood: 0.5 L (10-12% of total blood)
② Volume of the lungs: 3 L
③ Mammals and fish have a larger respiratory surface area at higher weights
④ Oxygen respiration in mammals is proportional to alveolar surface area
⑤ Obesity: Lack of respiratory area → limited oxygen supply → decreased activity
3. Lung ventilation (mammals)
⑴ Breathing pressure: Consumes 3-5% of total energy
① The lungs are passively ventilated with diaphragm and intercostal contractions connected to the pleura
○ The lungs themselves have no muscles and cannot actively contract
○ Thoracic cavity: The lungs are floating in the chest cavity and the chest cavity is a closed space
○ Pleura: Comprised of proximal and pleural pleura, pleural effusion in interstitial space (3-4 mL)
○ Pneumothorax: Perforation of the pleura due to infection or cuts
○ Gang: Thin space surrounding the lungs
○ Contractions of the diaphragm and intercostal muscles are transmitted to the lungs through the pleural effusion so that the lungs are passive contractions
○ Lung flexibility: More surfactant, less scar tissue increases lung flexibility
② Inspiration (Inhalation): Rib rise (external intercostal contraction), diaphragm descend (diaphragm contraction) → thoracic expansion → pressure drop → air inflow
③ Exhalation: Rib lowering (intercostal contraction), diaphragm rise (diaphragm relaxation) → thoracic contraction → pressure rise → air release
○ Less consumption of ATP during the exhalation process due to gravity and lung elasticity
④ Alveolar pressure, intrathoracic pressure change during breathing
○ Point 1. The pleural intraluminal pressure should be less than the alveolar pressure because the human body regulates the pleural cavity pressure to control the alveolar pressure
○ Point 2. The lungs show a wave graph because the air flows in when the pressure is lowered to offset the change.
○ Volumetric-pressure curve of the lung (link: / 1464): When inflating requires more pressure than when contracting

⑤ Disadvantages: Partial Pressure Slope Reduction, Backflow Gas Exchange ×
○ Due to the large amount of oxygen in the atmosphere, the disadvantages do not significantly affect species survival
⑵ Spirometry curve

① Parameter
○ Inspiratory residual volume
○ Expiratory residual volume
○ Residual volume
○ Spirometry = 1 tidal volume + absorbent reserve + phagocytic reserve
○ Total lung volume = 1 breath volume + absorbent reserve amount + eosinophilic reserve amount + residue amount
○ Intake volume = tidal volume + absorbent reserve
○ Functional residue amount = phagocytic reserve amount + residue amount
② Gas exchange at rest
○ Tidal volume: 500 mL
○ Ventilation rate: Respiratory Rate Per Minute. Typically 8-12 times per minute
○ Total waste ventilation: Ventilation rate × tidal volume = 8 × 500 mL / min to 12 × 500 mL / min = 3 to 6 L / min
○ Inspiration: Nitrogen 78%, Oxygen 21%, Carbon Dioxide 0.3%
○ Exhalation: Nitrogen 78%, Oxygen 17%, Carbon Dioxide 4%
○ 250 mL O2 / min influx into the blood → 360 to 600 L / day O2
○ 200 mL CO2 / min discharge into the lungs
○ Alveolar ventilation increased more than 20 times during exercise, alveoli blood flow increased 5-6 times
③ Dead space
○ Amount that does not contribute to gas exchange at one breath
○ Cause: Trachea from trachea to bronchioles lack respiratory epithelium and fail to participate in gas exchange
○ Degree: The anatomical dead space is about 140 mL, but the physiological dead space is about 150 mL, given that the bronchial dilated upon inspiration.
○ Alveolar ventilation volume (the amount of air reaching the alveoli) = ventilation rate (breath rate per minute) × (1 breath volume-dead space)
④ Ventilation volume and partial pressure of gas in the alveoli
○ Acidosis, Alkalosis General (See. 6)
○ Ventilation volume ↑ → CO2 release ↑ → respiratory alkalosis
○ Ventilation volume ↓ → CO2 in plasma ↑ → respiratory acidosis
⑶ Transpulmonary Pressure-Volume Graph
① Compliance
○ The degree to which the volume changes with pressure change
○ More surfactant increases the extension
② Inspiration: Confrontation between force to inflate alveoli and surface tension
○ Graphs that don’t seem to increase in volume
○ When treating surfactant: Reduced surface tension → Easy alveolar expansion → Moving graph in the direction of increasing volume
③ Exhalation: Strength of alveoli and surface tension strengthen each other
○ A graph that seems to increase in volume
○ When treating surfactant: Decrease in surface tension → negative alveolar contraction → move graph in the direction of increasing volume
4. Gas transport of blood
⑴ Breathing pigment: Special proteins that carry oxygen
① Hemocyanin: Breathing pigments of arthropods and molluscs, blue (including Cu)
② Hemoglobin: Breathing pigments of most vertebrates and invertebrates, red (including Fe)
③ Myoglobin: More oxygen affinity than hemoglobin, red (including Fe)
○ Diving mammals, heart and muscles are high in myoglobin
○ Myoglobin cannot enter the blood
⑵ Oxygen transport
① Function of hemoglobin: Oxygen transport
○ One red blood cell contains 250 million Hb → carries 1 billion molecules of oxygen (99%)
○ 198 mL / L of 200 mL / L of total blood oxygen
○ Less than 1% oxygen dissolved in plasma or red blood cell substrate
○ Respiratory pigment has higher saturation with higher oxygen partial pressure
○ Hemoglobin binds to oxygen in the lungs (100% saturation) and dissociates only about 30 to 40% at the tissue ends
② Structure: Allosteric enzyme, α2 β2 (quaternary structure, HbA), each unit consisting of heme and globin

○ Myoglobin only consists of tertiary structure
○ Heme: It has an organic ring structure called porphyrin, with Fe2+ in the center
○ Fetus: HbF (Hb Fetus) is present
○ Embryo ~ 8 weeks: ζ2 ε2
○ About 6 weeks pregnant, HbF begins to be produced in the liver
○ Around 8 months of pregnancy, HbA begins to form in the bone marrow
○ In newborns, 70% are HbF and 30% are HbA
○ Rapid HbA (Hb Adult) replacement between 3 and 6 months after birth (HbF destruction)
○ Oxygen affinity: α2 γ2 > α2 β2
○ Oxygen released from maternal hemoglobin binds to fetal hemoglobin
○ Cause: BPG binding site sequence difference, γ chain of HbF and β chain of HbA differ about 38% in amino acid sequence
○ BPG affinity: γ chain β chain (See. 4-⑶-④)
○ HbA2: About 2% of hemoglobin in adults (98% is HbA), α2δ2
○ See: Hemocyanin is a respiratory pigment with copper, not iron, found in arthropods and molluscs a lot.
③ Ligands that bind to Hb’s heme (competitive inhibition of oxygen)
○ oxy Hb: Hb + O2 → HbO2(red)
○ saturated oxy HB: Hb + 4O2 → Hb(O2)4
○ reduced Hb: Hb + H+ → HHb (reddish brown)
○ met Hb: OH- (Fe3+) occurs occasionally, but resolves itself in vivo
○ carboxy Hb: CO (affinity ) causes carbon monoxide poisoning
○ cyano Hb: Causes of death of CN- (affinity ) and cyanide (KCN)
○ (Note) Carbon dioxide and 2,3-BPG bind to globin and do not act as an inhibitor, but lower red blood cell oxygen transport ability.
④ Cooperative: In the fourth structure, when the substrate is bound to one monomer, the affinity of the substrate of the surrounding monomer increases.

○ Myoglobin forms the shape (MM type) expected by the Michaelis-Menten equation because of the constant affinity of the substrate.
○ Myoglobin is not an allosteric protein such as hemoglobin
○ Myoglobin has higher oxygen affinity than hemoglobin, so oxygen storage at low oxygen partial pressure; The presence of multiple myocytes
○ Seals, which are submersible mammals, store about twice as much oxygen per kilogram of body weight as myoglobin ↑.
○ Hemoglobin shows the sigmoid type (S-shape) because the affinity of the substrate is gradually increased
○ Hemoglobin is an allosteric protein to which two or more ligands can bind
○ Even if only one oxygen molecule is bound to hemoglobin, the subunit becomes a structure with high affinity with oxygen
○ Conversely, only one oxygen molecule escapes from saturated hemoglobin, resulting in a low oxygen affinity.
○ Stability: Oxygen carrying capacity is greatly reduced even when the partial pressure of oxygen in alveoli and arterial blood reaches 100 mmHg to 60 mmHg ×
⑶ Bore effect: Oxygen Affinity Change of Hemoglobin by Four Factors (pH, pCO2, Temperature, 2,3-BPG)


① H+ effect
○ [H+] ↑ → pH ↓ → Changes in ionic bonds in Hb (eg histidine of β chain) → Hb conformation change → oxygen affinity ↓
○ Oxygen and dissociated hemoglobin combine with hydrogen ions to prevent acidification of blood
○ Ion Bond Change 1: -COOH ↔ -COO- + H+ (Place: Globin)
○ Ion Bond Change 2: -NH2 + H+ ↔ -NH3+ (Location: Globin)
○ Oxygen affinity change during exercise 1: PH ↓ → oxygen affinity ↓ due to lactic acid and fatty acid production
② CO2 effect
○ CO2 ↑ → CO2 binding or acid increase at N-terminus → Hb conformational change → oxygen affinity ↓
○ CO2 bonding at the N-terminus
○ Acid increase: If pCO2 is high, pH is reduced to H + derived from carbonic acid.
○ Reduced oxygen affinity allows hemoglobin to dissociate oxygen better in tissue cells
③ Temperature effect
○ Temperature ↑ → Hb conformation change → Oxygen affinity ↓
○ Actively metabolizing or exercising cells release heat
○ Enzymes rapidly lose their activity as their intramolecular bonds weaken at temperatures after their activation temperature
④ 2,3-BPG (2,3-bisphosphoglycerate) effect

○ 2,3-BPG: Active production of glycolysis, isomer of 1,3-BPG, an intermediate product of glycolysis
○ Mammalian erythrocytes have high concentrations of 2,3-BPG
○ 2,3-BPG ↑ → Stabilizes deoxyhemoglobin by combining with β globin in the middle of hemoglobin → additional oxygen affinity ↓
○ Oxygen affinity change during exercise 2: Tissue cell oxygen debt phenomenon → Some G3Ps convert to 2,3-BPG → Oxygen bond in β globin ↓
⑤ When moving to a high altitude mountain
○ 1st. Reduction of partial pressure of oxygen in the atmosphere
○ 2nd. Decreases the amount of oxygen binding of hemoglobin in the lungs
○ Increase respiratory rate to compensate for insufficient oxygen binding
○ Respiratory algorithm: Increasing respiratory rate releases excess CO2, increasing blood pH
○ 3rd. Decreased oxygen supply to tissue cells → Increased 2,3-BPG in red blood cells
○ Reduced oxygen affinity of hemoglobin releases more oxygen from oxygen hemoglobin
○ 4th. Reduced oxygen supply to the kidneys
○ 4th-1st. Increased erythropoietin secretion in the kidneys
○ 4th-2nd. Promote red blood cell production in bone marrow → increase red blood cell count
⑷ Carbon dioxide transport
① Plasma: 8%, simple diffusion (melting)
○ CO2 (g) → CO2 (aq)
② Combined with hemoglobin: HbCO2, about 22%
③ Bicarbonate ion: HCO3-, about 70%
○ 1st. CO2 (aq) simply diffuses from plasma to red blood cells
○ 2nd. Promoted by CO2 (aq) + H2O (l) → H2CO3 (aq), carbonic anhydrase (CA)
○ 3rd. H2CO3 → H+ + HCO3-
○ 4th. H+ combines with Hb to become HHb (See. ⑶-①)
○ 5th. HCO3- is one-to-one reverse cotransport with Cl- and discharged out of plasma
○ 6th. Osmotic pressure causes water to enter as Cl- increases in erythrocytes → volume increases

⑸ Pulmonary and body circulation: Circulation and respiratory system harmony

① Pulmonary Circulation (12% Blood Retention)
○ Right ventricle → Pulmonary artery → Pulmonary capillary → Pulmonary vein → Left atrium
○ Blood with O2↓, CO2↑ → Blood with O2↑, CO2↓
② Circulation (79% blood retention)
○ Left ventricle → aorta → artery → capillary → vein → vena cava → right atrium
○ Blood with O2↑, CO2↓ → Blood with O2↓, CO2</sub↑
○ Aortic partial pressure: 80 to 100 mmHg
○ Venous oxygen partial pressure: 40 mmHg
○ Supply nutrients and oxygen to tissue cells
5. Control of breathing
⑴ Control of number: Cortex → Cortex spinal cord → Motor neurons
⑵ Self-regulating central: Pontoon, training → voluntary, rhythmic activity

① Soft water: Basic breathing control
○ Soft water is more affected by carbon dioxide than oxygen
② Pons: Adjusts for smooth transition between inspiration and exhalation, breathing rate
③ Input and receiver
○ Chemical receptors in the central nervous system (especially cerebrospinal fluid) (pO2, pCO2, H+)
○ H+ cannot cross the brain-vascular barrier so chemical receptors determine H+ by the amount of CO2
○ Increase metabolism through exercise → CO2 ↑ → Increase respiration → Excessive CO2 emissions → Normalize pH
○ Input of chemical receptors (H+, pO2, pCO2) of aortic bodies (next to the aortic arch) and carotid bodies (next to the carotid artery)
○ O2 concentration does not have a significant effect on breathing, but increases respiration rate when O2 levels are low
○ Plasma epinephrine and potassium concentration receptors
○ Muscle and joint kidney receptor input
○ Renal Receptor Input to Lung
○ Stimulation (temperature, etc.) input through other receptors and under Thalamus
④ Breathing control process
○ Breathing exercise: Sympathetic stimulation, adrenaline secretion
○ Respiratory movement suppression: Parasympathetic stimulation, acetylcholine secretion
6. Acidosis and Alkalosis
⑴ Steady state
① PH: 7.41 to 7.45
② O2: 40 mmHg (tissue) or more 100 mmHg (lung) or less
③ CO2: 40 mmHg (lung) or more 46 mmHg (tissue) or less
④ HCO3-: 24 mmEqmol
⑵ Acidosis and Alkalosis
① Acidosis: pH 7.35 or less
② Alkalosis: pH 7.45 or more
⑶ Metabolic alkalosis: Metabolism Excessive HCO3-
① Excess HCO3- reacts with H+ resulting in high pH
② Compensation: Increased partial pressure of CO2 by lowering breathing rate to lower pH
③ Example: Vomiting (exhaust acid from the stomach)
⑷ Metabolic acidosis: If HCO3- is low due to metabolism
① Less HCO3sup>-</sup>, H+ remains in the blood, resulting in lower pH
② Compensation: Lowers CO2 partial pressure by increasing respiration rate to increase pH
③ Example: Diarrhea (Bicarbonate Release)
⑸ Respiratory alkalosis: When the partial pressure of CO2 is lowered in relation to breathing
① Lower CO2 partial pressure results in higher blood pH
② Compensation: Suppresses HCO3-reaction to lower pH
③ Example: Hyperventilation, limited lung disease (e.g., Pulmonary fibrosis)
⑹ Respiratory acidosis: High CO2 partial pressure associated with respiration
① Low CO2 pH due to no CO2 emissions
② Compensation: Activate HCO3<sup-</sup> reaction to increase pH
③ Example: Obstructive pulmonary disease (e.g., asthma)
7. Lung disease
⑴ Acidosis and Alkalosis
① Normal Conditions
○ pH: 7.41 ~ 7.45
○ O2: ≥ 40 mmHg (tissue), ≤ 100 mmHg (lungs)
○ CO2: ≥ 40 mmHg (lungs), ≤ 46 mmHg (tissue)
○ HCO3-: 24 mEq/mol
② Acidosis and Alkalosis
○ Acidosis: When pH is below 7.35
○ Alkalosis: When pH is above 7.45
Figure 10. Acidosis and Alkalosis
③ Metabolic Alkalosis: Caused by excessive HCO3- due to metabolism
○ Excess HCO3- binds to H+, raising the pH
○ Compensation: Decreased respiratory rate to raise CO₂ partial pressure and lower pH
○ Example: Vomiting (loss of acidic gastric content)
④ Metabolic Acidosis**: Caused by depletion of HCO3- due to metabolism
○ Reduced HCO3- leaves more free H+ in blood, lowering pH
○ Compensation: Increased respiratory rate to reduce CO2 partial pressure and raise pH
○ Example: Diarrhea (loss of bicarbonate from the body)
⑤ Respiratory Alkalosis**: Caused by reduced CO2 partial pressure due to respiration
○ Lower CO2 leads to elevated blood pH
○ Compensation: Inhibition of HCO3- production to lower pH
○ Example: Hyperventilation, restrictive lung diseases (e.g., pulmonary fibrosis)
○ Narrowing of blood vessels including cerebral vessels may occur to prevent CO2 loss, causing dizziness
○ Treatment for hyperventilation: Breathing into a paper bag to rebreathe exhaled CO2
⑥ Respiratory Acidosis: Caused by increased CO2 partial pressure due to impaired respiration
○ Retention of CO2 lowers blood pH
○ Compensation: Activation of HCO3- production to raise pH
○ Example: Obstructive lung diseases (e.g., asthma)
⑵ Lung Cancer
① Type 1. SCLC (Small Cell Lung Cancer): Accounts for 15% of all lung cancers.
○ Chemotherapy and radiation therapy are the primary treatments
○ Originates from neuroendocrine cells
○ Most cases are associated with heavy smoking
○ Surgery is rarely performed, so research samples are relatively limited
② Type 2. NSCLC (Non-Small Cell Lung Cancer): Accounts for 85% of all lung cancers.
○ Surgery is the primary treatment; chemotherapy and radiation are secondary
○ 2-1. LUSC (Lung Squamous Cell Carcinoma): 45% of all lung cancers
○ Smoke-driven
○ Involves KRAS
○ Originates from basal epithelial cells
○ 2-2. LUAD (Lung Adenocarcinoma): 45% of all lung cancers
○ EGFR mutation-driven
○ Combination therapy with immune checkpoint inhibitors (ICI) is being explored
○ Originates from alveolar type II epithelial cells
○ 2-3. LCC (Large-Cell Carcinoma): Originates from various epithelial cells
③ Lung Cancer and Smoking
○ Tar and fine particles remain on lung surfaces, causing mutations and cancer
○ Characteristics of cigarettes:
○ Contain around 100,000 chemicals
○ About 20 classified as Group A carcinogens
○ Major harmful substances: tar, carbon monoxide, nicotine
○ Tar: Cigarette residue, ~10 mg per cigarette
○ Contains ~40 carcinogens
○ Penetrates the bloodstream and destroys cells
○ Disrupts immune system, induces chronic inflammation
○ Damages cilia and elastin
○ Carbon Monoxide:
○ Product of incomplete combustion
○ Most abundant substance in cigarette smoke
○ Main cause of chronic hypoxia, premature aging, and atherosclerosis
○ Nicotine: ~0.1 to 0.6 mg per cigarette
○ Reaches the brain in ~7 seconds
○ Addictive, narcotic, toxic; also used in pesticides and herbicides
○ Increases blood pressure
○ Other toxic substances:
○ Benzo[a]pyrene: Carcinogen
○ Dimethylnitrosamine: Carcinogen
○ Hydrogen cyanide: Lethal gas chamber toxin
○ Naphthylamine: Preservative
○ Naphthalene: Moth repellent
○ DDT: Pesticide
⑶ Chronic Obstructive Pulmonary Disease (COPD)
① Symptoms: Increased mucus and narrowed airways (due to elastin dysfunction) increase airway resistance and cause ventilation impairment
② Feature 1: Total lung capacity and residual volume are higher than normal (compensatory)
③ Feature 2: Respiratory function is always lower than normal
④ Rolipram: A clinical drug used to treat COPD
⑤ Example 1. Chronic Bronchitis:
○ Excessive mucus secretion in bronchi → chronic inflammation in lower airways
⑥ Example 2. Asthma:
○ Causes: Allergic reactions, viral infections, etc.
○ Symptoms: Alveolar constriction, increased mucus secretion, increased airway resistance, chronic inflammation
○ Fine particles exacerbate asthma
⑦ Example 3. Emphysema:
○ Caused by scar tissue formation due to bronchitis and asthma
○ Destruction and blockage of small airways → reduced alveoli count and surface area
○ Irreversible
⑷ Restrictive Lung Diseases
① Symptoms: Reduced lung compliance (ability to expand), leading to ventilation impairment
② Feature 1: Total lung capacity and residual volume are lower than normal
③ Feature 2: Respiratory function is comparable to normal within a limited range
④ Example 1. Pulmonary Fibrosis
○ Subtypes:
○ IPF (Idiopathic Pulmonary Fibrosis)
○ cHP (Chronic Hypersensitivity Pneumonitis)
○ NSIP (Nonspecific Interstitial Pneumonia)
○ Sarcoidosis
○ Unclassifiable ILD
○ Consolidation: Lung appears completely white
○ Crazy paving: Thickened blood vessels
○ Treatment: Nintedanib, Pirfenidone (target tyrosine kinases)
⑤ Example 2. Pneumoconiosis, Tuberculosis
⑥ Example 3. Occupational Lung Disease
○ Fine dust (asbestos, coal dust, silica, paper dust, pollen, etc.) accumulates in macrophages
○ Scar tissue replaces lung tissue → fibrous cysts, reduced lung flexibility
⑸ Pulmonary Edema
① Definition: A condition in which fluid leaks into alveoli as pulmonary veins exceed lymphatic drainage capacity
○ Lymphatic drainage: Ability to recover interstitial and lymph fluid from pulmonary capillaries
② Causes**:
○ Heart failure → increased pulmonary venous pressure
○ Decrease in external air pressure
③ Symptoms: Causes shortness of breath
⑹ ARDS (Acute Respiratory Distress Syndrome)
① Example: Post-SARS-CoV-2 lung disease
Input: 2015.7.19 11:19