Respiratory Control

Question 1

Minute Ventilation =

Answer 1

Frequency X Tidal Volume

Question 2

Inspiration occurs when what nerve is active?

Answer 2

Phrenic N.

Question 3

What are the 4 respiration control centers in the brain?

Answer 3

1. Pre-Botzinger Complex
2. Pontine Respiratory Group (PRG)
3. Dorsal Respiratory Group (DRG)
4. Ventral Respiratory Group (VRG)

Question 4

Pre-Botzinger Complex

Answer 4

Generates the core timing (frequency) of the respiratory rhythm

Question 5

What brain center generates the core timing (frequency) of the respiratory rhythm?

Answer 5

Pre-Botzinger Complex

Question 6

What brain center helps control the respiratory rhythm frequency by stopping inspiration?

Answer 6

Pontine Respiratory Group (PRG)

Question 7

Pontine Respiratory Group (PRG)

Answer 7

Helps control the frequency of the respiratory rhythm by STOPPING INSPIRATION

Question 8

What occurs when the PRG is lesioned?

Answer 8

Apneusis - failure to stop inspiration

Question 9

Apneusis

Answer 9

Failure to stop inspiration

Question 10

Failure to stop inspiration

Answer 10

Apneusis

Question 11

What areas of the brain contribute to determining the timing/frequency of the respiratory rhythm?

Answer 11

Pre-Botzinger Complex

Pontine Respiratory Group

Question 12

Dorsal Respiratory Group (DRG)

Answer 12

95% premotor to Phrenic N.

= Generates a pattern appropriate to the circumstance

Question 13

What brain center contains 95% premotor to Phrenic N.?

Answer 13

Dorsal Respiratory Group (DRG)

Question 14

Ventral Respiratory Group (VRG)

Answer 14

Premotor to other inspiratory and expiratory muscles

Question 15

What are the regions of the VRG?

Answer 15

Rostral - Premotor to inspiratory muscles

Caudal - Premotor to expiratory muscles

Question 16

What areas of the brain contribute to determining the depth of the respiratory rhythm (tidal volume)?

Answer 16

Dorsal Respiratory Group

Ventral Respiratory Group

Question 17

Apnea

Answer 17

Failure to turn off expiration (NO inspiration)

Question 18

Failure to turn off expiration (NO inspiration)

Answer 18

Apnea

Question 19

Damage to ____ causes Apneusis

Answer 19

Pons

Question 20

Damage to ____ causes Apnea

Answer 20

Medulla or spinal cord

Question 21

What do chemoreceptors do?

Answer 21

Neurons that INCREASE firing rate in response to a chemical change

Question 22

Where are central chemoreceptors located?

Answer 22

Ventral surface of medulla

Question 23

What do central chemoreceptors come into contact with?

Answer 23

CSF - cerebrospinal fluid

Question 24

What molecule crosses the blood-brain barrier and contacts the central chemoreceptors?

Answer 24

CO2

– increased CO2 means there is decreased O2 and we need to breathe

Question 25

What is the central chemoreceptors response based on?

Answer 25

PaCO2 in the blood

Question 26

Describe how the central chemoreceptors increase their firing rate as CO2 reaches the CSF at the ventral surface of the medulla

Answer 26

- CO2 reaches CSF and is mixed with H2O - Carbonic Anhydrase is present and creates H2CO3 - H2CO3 dissociates to H+ and HCO3- - H+ activates the central chemoreceptor increase firing rate!!!

Question 27

What molecule activates the central chemoreceptor to increase firing rate?

Answer 27

H+

Question 28

Where does the axon of the central chemoreceptor go to?

Answer 28

Pre-Botzinger Complex

Question 29

Once the axon of the central chemoreceptor reaches the Pre-Botzinger Complex, then what is the cascade of the signal?

Answer 29

Pre-Botzinger DRG/VRG Phrenic N. Diaphragm

Question 30

What chemoreceptors respond with quick changes?

Answer 30

Peripheral chemoreceptors

Question 31

Where are the majority of the peripheral chemoreceptors?

Answer 31

Carotid Body

Question 32

What senses O2 in the peripheral chemoreceptors?

Answer 32

Type 1 Glomus cell

Question 33

When the peripheral chemoreceptors sense the low O2, what do they increase/decrease?

Answer 33

ROS, Lactate and decrease ATP

Question 34

When Peripheral chemoreceptors increase ROS, lactate and decrease ATP what does this cause?

Answer 34

K+ leaky channels SHUT | -- Cells depolarize!

Question 35

As the peripheral chemoreceptors are starting to depolarize once the leaky K+ channels shut, then what enters the cell?

Answer 35

CALCIUM | -- Cells depolarize further and generate an action potential

Question 36

What do peripheral chemoreceptors end up releasing?

Answer 36

Dopamine

Question 37

With what nerve can peripheral chemoreceptors send action potentials?

Answer 37

CN IX

Question 38

What are the mechanoreceptors?

Answer 38

Pulmonary Stretch Receptors

Question 39

Where are slowly and rapidly adapting pulmonary stretch receptors located?

Answer 39

Airways

Question 40

Describe how slowly adapting pulmonary stretch receptors stop inspiration

Answer 40

Increased size of lungs Increases the stretch in the airways Sends an action potential via vagus nerve STOPS inspiration

Question 41

When are slowly adapting pulmonary stretch receptors critical?

Answer 41

Infancy | Adults when exercising

Question 42

What activates rapidly adapting pulmonary stretch receptors to produce a cough?

Answer 42

Airway irritation via CN X

Question 43

Rapidly adapting pulmonary stretch receptors are ______

Answer 43

Protective

Question 44

Slowly adapting pulmonary stretch receptors are used for _____

Answer 44

Normal breathing

Question 45

Where are juxtacapillary (J) receptors?

Answer 45

By alveolar capillaries

Question 46

What activates J receptors?

Answer 46

Pulmonary edema

Question 47

When the J receptors are active, what do they cause to happen?

Answer 47

Dry cough and rapid/shallow breathing

Question 48

How does the Cortex influence breathing?

Answer 48

BYPASSES the medullary centers and directly contacts muscles of respiration