Neuronal Control of CV and Respiration

Question 1

similarities between cardio and resp control systems

Answer 1

continuous neuronal activity required for normal function for both- need intact C4 and above

both require afferent info from periphery- carotid sinus- blood and carotid body- pCO2

neuronal site in brainstem are both within the solitary nucleus, although involving different neurons

higher CNS can have drastic effects on both

Question 2

differences between cardio and resp control systems

Answer 2

heart- can function with only SA pacemaker and has some inherent autoregulatory capacity in vessels

lungs- pacemaker cells reside in brainstem via phrenic nerve

Question 3

major groups of brainstem neurons for CV regulation

Answer 3

NTS- afferent input from vagal (aortic sinus) and glossopharyngeal (carotid sinus)

nucleus ambiuous- site of vagal neurons that are parasympathetic efferent to the heart

rostral ventrolateral medulla- pressor center

caudal ventrolateral medulla- depressor center

Question 4

higher CNS sites affecting CV regulation

Answer 4

areas involved in emotional behaviors, like amygdala, insula, hypothalamus, and periaqueductal gray, can affect CV regulation

Question 5

SUDEP

Answer 5

sudden unexpected death in elipsy- related to hypoxemia

Question 6

sudden death in overwhelming emotion

Answer 6

excessive sympathetic stimulation in animals w/ lowered threshold for v fib

excessive parasympathetic- bradycardia precipitating arrythmias

Question 7

neurogenic hypertension

Answer 7

intermittent stress related increases in sympathetic activity to vascular smooth muscle resistance, causing increased resistance and BP, causing hypertrophy in the resistance muscles and a perminent increase in BP

Question 8

respiratory regulation

Answer 8

pontine respiratory group in kolliker fuse nuclei

dorsal respiratory group in NTS

ventral respiratory group w/ nucleus ambiguous and pre-botzinger complex

also important- airway cranial nerves

Question 9

prebotzinger complex

Answer 9

in VRG, source of respiratory rhythm

Question 10

examples where higher CNS affects breathing

Answer 10

sleep
apnea-collapse of upper airway d/t decreased airway muscle activity or tongue
hypoventilation- brain not as responsive to increased PCO2 as when awake

emotion
psychogenic hyperventilation- mediated by amygdala

volition-
voluntary control of breathing