Respiratory 29

Question 1

Where is the Rhythm of breathing established?

Answer 1

In the CNS

Question 2

Where is breathing initiated?

Answer 2

In the medulla by specialized neurons

Question 3

What are the three important regions that control breathing in the brainstem?

Answer 3

• The pontine respiratory group
• Dorsal respiratory group
• Ventral respiratory group

Question 4

Which part of the brainstem are respiratory rates generated?

Answer 4

The ventral respiratory group

Question 5

What is breathing modified by?

Answer 5

Higher structures of the CNS and inputs from central and peripheral chemoreceptors and mechanoreceptors in the lung and chest wall

Question 6

what must neuronal networks establish for contraction of the respiratory muscles?

Answer 6

Automatic rhythm

Question 7

At what level does the neural control of breathing occur?

Answer 7

At the level of the brainstem

Question 8

What is the most important respiratory group in the brainstem?

Answer 8

The ventral respiratory group

Question 9

Why is the ventral respiratory group most important?

Answer 9

Because both the inspiratory rhythm generator and the expiratory rhythm generator are located in this area

Question 10

What kind of complex is the inspiratory rhythm generator?

Answer 10

A PreBötzinger complex (PreBötC)

Question 11

What is the PreBötzinger complex?

Answer 11

A group of neurons in the ventral respiratory group that generate rhythmic contractions from the six month of gestation until your last breath

Question 12

Through what pathway does the PreBötzinger complex act?

Answer 12

Via the polysynaptic pathway

Question 13

When do PreBötzinger neurons fire?

Answer 13

Everytime there is an inspiratory effort

Question 14

What is the Parafacial respiratory group (pFRG)?

Answer 14

A group of neuron in the ventral respiratory group important for generation rhythmic excitatory active expiratory rhythmic activity that excites expiratory muscles

Question 15

What would happen if the Parafacial neurons did not have any influence from higher levels of the brain or the peripheral chemoreceptors?

Answer 15

There would be no change in tidal volume or respiration frequency

Question 16

What kind of changes must neuronal networks adjust to for breathing?

Answer 16

• Metabolic demands
• Varying mechanical conditions (posture changes)
• Non-ventilatory behaviors (speaking, sniffing, eating)
• Pulmonary and non-pulmonary diseases

Question 17

Where is the Rhythm of breathing generated?

Answer 17

In the ventral respiratory group (VRG) in the medulla

Question 18

What neurotransmitters influence neural control of breathing?

Answer 18

•5-HT (serotonin)
•NE peptides
•Glutamate
Orexin

Question 19

What is meant by volitional suprapontine influences?

Answer 19

Voluntary changes in breathing when you are talking and for example want to take a big breath

Question 20

What happens once breathing is generated at the level of the ventral respiratory group by the activity of the PreBötzinger complex and the parafacial respiratory group?

Answer 20

The excitatory drive moves down the neuron pathways and activates respiratory muscles

Question 21

What is rhythmic activity influenced by?

Answer 21

Sensory and neuromodulatory inputs originating from different regions within and outside the CNS

Question 22

What is the pathway to excite the Diaphragm and Ext. Intercostal muscles for inspiration?

Answer 22

The PreBötzinger complex excites INS premotor neurons in the rostral VRG. This then excites phrenic and thoracic motor neurons in the cervical and thoracic spinal cord which excites the diaphragm and the external intercostals

Question 23

What is the pathway to excite the tongue and upper airway muscles for inspiration?

Answer 23

The PreBötzinger complex excite the premotor neurons in the Rostral VRG and parahypoglossal region PXII. They then excite cranial motor neurons in the medulla which excite the tongue and upper airway

Question 24

Which neurons are initially responsible for active expiration?

Answer 24

The pFRG neurons

Question 25

What is the pathway for exciting the INT. Intercostal and abdominal muscles for active expiration?

Answer 25

The pFRG excite EXP premotor neurons (caudal VRG) which excite thoracic and lumbar motor neurons in the spinal cord which excite the INT. Intercostal and abdominal muscles