4-Regulation of Respiration

Question 1

intrinsic neural control

Answer 1

og @ pons and medulla
-sends efferent impulses to respir muscles

also cerebral cortex for voluntary control

Question 2

ventral respiratory group

VRG

Answer 2

neurons are inspiratory and expiratory
-esp powerful signals during active expir for abdom muscles

@medulla bilaterally

Question 3

pre-botzinger complex

PBC

Answer 3

central pattern generator for rhythm of breathing
@VRG
-innvervates inspriatory neurons in VRG and DRG

Question 4

dorsal respiratory group

DRG

Answer 4

mainly inspiratoyr
@dorsal medulla in nucleus tractus solitatrius

recieve input from pre-botz

Question 5

pontine respir group

Answer 5

transmit inhib signals to inspir neurons of DRG
-limit inspiration

Question 6

metabolic acidosis

Answer 6

dec HCO3/bicarb

requires dec PCO2 to keep pH the same
-inc alveolar vent

Question 7

metabolic alkalosis

Answer 7

inc bicarb so inc PCO2 to keep pH
-dec alveolar vent

Question 8

respiratory avidosis

Answer 8

inc PCO2
-acute resp = small inc bicarb bc kidneys respond slowly
-chronic = large inc bicarb, pH normalized

not breathing enough, hypoventilatin

Question 9

respiratory alkalosis

Answer 9

dec PCO2
-acute = small dec bicarb bc kidneys slow
-chronic = large dec bicarb, pH normalized

hyperventilation

Question 10

pH =

Answer 10

bicarb/ pCO2

Question 11

CO2 chemoreceptors

Answer 11

high CO2 = inc ventilation bc stim chemoreceptors (central and peripheral)

low pH only affets peripheral chemos, inc vent

Question 12

apneic threshold

Answer 12

hold breath longer bc driven PCO2 below apneic threshold

hyperventilation drives down PaCO2 so drive to breathe is reduced

Question 13

central chemoreceptors

Answer 13

brain nuclei (spread throughout, multi) sensitive to CO2/H+

CO2 readily diffuses across BBB but not H+
CO2 causes inc H+ in CSF

Question 14

peripheral chemoreceptors

Answer 14

as PO2 dec = inc alveolar ventilation

aortic body chemorecptors + carotid body (main type II glomus cells)
-sens to O2 tension reductions so inc respir and BP

Question 15

hyoxia inhibits

Answer 15

K+ channels so depolarize and Ca influx

Question 16

synergistic effect of periperal chemo

Answer 16

steeper slope = greater inc inalveolar vent for given inc in PCO2

lower PO2 + lower pH enhance vent resp to incs in PCO2

Question 17

sensory integration site

Answer 17

tractus solitarius has vagal and glossopharyngeal nerves that transmit sensory signals into respir center
-peripheral chemos + baroreceptors + lungs

Question 18

central command

Answer 18

during strenuous exercise O2 consumption and CO2 formation inc

stable arterial pressures and pH bc brain transmits to excite respir (feedforward signals to inc vent)

Question 19

signals from higher brain centers modulated by

Answer 19

1. input from peripheral chemoreceptors
2. type III and IV muscle afferents are sensitive to stretch and metabolites (from muscle contraction)

Question 20

airway irritant receptors

Answer 20

@ epi of trachea, bornchi, bronchioles
-coughing and sneezing + bronchoconstriction and inc mucus production

Question 21

pulmonary juxtacapillary receptors

Answer 21

sensory nerve endings in alveolar walls
-engorge of capillaries with blood from congestion or edema = apnea > tachypnea, bradycardia, hypotension, feeling dyspnea

Question 22

kussmaul breathing

Answer 22

diabetic ketoacidosis (metabolic acidosis)
super low pH drives fast, deep breaths

Question 23

biot’s breathing

Answer 23

ataxic, shallow irregular apnea
-brain stem injury or stroke

Question 24

obstructive sleep apnea

Answer 24

-upper airway collapse during sleep = surges in neural activity

poor notcuranl sleep quality + ensuing daytime fatigue + cog dysfunction
-risk factor for systemic hypertension, cardio dz, stroke, abnormal glucose metabolism

Question 25

risk factor for sleep apnea

Answer 25

age, male, obesity, family hx, menopause, craniofacial abnormalities