Control of Ventiliation

Question 1

How is ventilation controlled?

Answer 1

Negative Feedback Loop

Receptor
—> integration center
—> effector

Question 2

What are the receptors for ventilation control?

Answer 2

1. Central Chemoreceptors
2. Peripheral Receptors
3. Stretch receptors
4. Irritant receptors

Question 3

Central Chemoreceptors

Answer 3

• In ventral medulla oblongata
• monitors CSF- product of blood
• monitors pH

too low pH (acidic) => Hypercapnia (↑ RR)
cause: drugs, alcohol, respiratory depressant

Too high pH (basic) => Hypocapnia (↓ RR)
cause: hyperventiliation
clinically created w/ respirator too high

Question 4

Peripheral Chemoreceptors

Answer 4

monitor pH & stimulate medullary respiratory centers:

Carotid sinus
-glossopharyngeal CN 9

Aorta
- Vagus CN 10

Question 5

Stretch Receptors
- what also called?
- what do?
- where located?

Answer 5

= Mechanoreceptors
- Within smooth muscle of the airway
- Hering Breuer reflex
- prevent over inflation of the lungs

Question 7

What are the integration centers for control of ventilation?

Answer 7

1. Medullary Respiration Center
   
   • Ventral respiration
     Group (VRG):
     responsible for Eupnea
     pacemaker for breathing (12- 15)
   • Dorsal respiration
     Group (DRG):
     receve infor from the peripheral chemoreceptors and modifying VRG
2. Pontine Respiratory Center
   
   • Pneumotaxic center:
     Off switch
   • Apneustic center:
     On switch
     conscious
     info from cerebral cortex & limbic system
     allow from smooth transition of breathing

Question 8

What are the Medullary respiration centers?
What do they do?

Answer 8

2 nuclei (cluster of neuron cell bodies with a common function)

1. Medullary Respiration Centers
   
   • Ventral respiration
     Group (VRG):
     responsible for Eupnea
     pacemaker for breathing (12- 15)
   • Dorsal respiration
     Group (DRG):
     receve infor from the peripheral chemoreceptors and modifying VRG

Question 9

What are pontine respiratory centers?

Answer 9

2 nuclei (cluster of neuron cell bodies with a common function)

• conscious breathing
• info from cerebral cortex & limbic system
• allow for smooth transition of breathing

1. Pneumotaxic center:
   Off switch
   
   • conscious tell
     ourselves to stop
     breathing
2. Apneustic center:
   On switch
   
   • conscious &
     unconscious control
     of breathing

Question 10

Effectors for control of ventilation? What are the nerves that send the signal to these?

Answer 10

skeletal muscles of respiration

1. Diaphragm (Primary)
   -phrenic nerve
2. Intercostal Muscles
   - external & internal
   - thoracic nerves
3. Scalene musle
   - cervical nerves
4. Sternocleidomastoid
   - accessory nerve
5. Abdominal muscles