#2 Zhu - Regulation of Respiration Flashcards
What are the three respiratory control centers?
1 - Medullary Respiratory Center
2- Pneumotaxic Center
3 - Apneustic Center
What are the components of the Medullary Respiratory Center?
Dorsal Respiratory Group (DRG) I DRAG (Intrinsic Dorsal Respiratory Automaticity Group)
Ventral Respiratory Group (VRG)
VERG (Ventral Expiratory Respiratory Group)
Pre-Botzinger Complex
What is the Dorsal Respiratory Group responsible for?
Intrinsic periodic firing
Automaticity
Responsible for the basic rhythm of ventilation
Ramp style inspiration
Dorsal Respiratory Group (DRG) I DRAG (Intrinsic Dorsal Respiratory Automaticity Group)
What is the Ventral Respiratory Group responsible for?
If DRG increases, VRG activates to increase expiration.
Quiescent during normal breathing.
What is the Pneumotaxic Center responsible for?
It has an inhibitory effect on the dorsal inspiratory group. Regulates respiratory rate and volume.
Deeper slower breathing
What is the Apneustic Center responsible for?
Experimental: excitatory effect on the dorsal inspiratory group
Prolonged inspiratory gasps
What is Congenital Central Hypoventilation Syndrome?
Individuals have to tell themselves to breath. They have lost automaticity.
What are the two types of chemoreceptors in the regulation of respiration?
Central Chemoreceptors
Peripheral Chemoreceptors
Where are the central chemoreceptors located in the respiratory system?
Ventral surface of the medulla
NOT part of the respiratory control centers
What is the stimulus for the central chemoreceptors in the respiratory system?
Increased H+ in the Extracellular Fluid and Cerebrospinal Fluid
(sensitive to PCO2 change in the blood; acute effect)
Where are the peripheral chemoreceptors located in the respiratory system?
Carotid bodies
Aortic bodies
What are the stimuli for the peripheral chemoreceptors in the respiratory system?
Decreased arterial PO2 (hypoxemia)
Increased arterial PCO2
Increased arterial H+ (carotid bodies)
How quick is the respiratory response to the peripheral chemoreceptors?
Rapid response
Where is the major response to increased arterial PCO2?
Central chemoreceptors (ventral surface of medulla)
What will magnify the response of the central chemoreceptors?
Decreased arterial PO2
Synergistic effect
Which chemoreceptors are stimulated by decreased arterial pH?
Peripheral chemoreceptors
Peripheral = pH
What are some other receptors found in the respiratory system beside the central and peripheral chemoreceptors?
Lung receptors Nose and Upper airway receptors Joint and muscle receptors Gamma system Arterial baroreceptors Pain and temperature
What three receptors are found in the lung?
Pulmonary stretch receptors
Irritant receptors
Juxtacapillary receptors (C fibers)
Where is the location of the pulmonary stretch receptors?
Location: Within airway smooth muscles
What is the stimulus of the pulmonary stretch receptors?
distension of the lung
Tidal volume >= 1 L
What is the purpose of the pulmonary stretch receptors?
Prevent excess lung inflation
“Hering-Breuer Inflation Reflex”
Where is the location of the irritant receptors?
Between airway epithelial cells
What is the stimulus of the irritant receptors?
Cigarette smoke
Noxious gases
What is the effect of the irritant receptors?
Bronchoconstriction
Hyperpnea
Where is the location of the juxtacapillary receptors?
In the alveolar walls close to the capillaries
What is the stimulus of the juxtacapillary receptors?
Engorgement of the capillaries
What is the effect of the juxtacapillary receptors?
Rapid, shallow breathing
Dyspnea
During moderate exercise, after ventilation increases what causes pulmonary vascular resistance to decrease?
Recruitment
Distention
What happens to the diffusion capacity during moderate exercise?
Increases
What happens to the ventilation-perfusion mismatch during moderate exercise?
Decreases after the respiratory response
