CNS Organization

Question 1

ANS monitors? integration of 4 things?

Answer 1

monitors internal environment. integration of cognition, emotions, memory + learning

Question 2

9 autonomic centers

Answer 2

nucleus of the solitary tract. nucleus ambiguus. locus coeruleus (A5 NA). ventrolateral medulla. rostral ventrolateral medulla. caudal raphe nuclei. PAG. hypothalmic nuclei. parabrachial region

Question 3

what 5 centers are labeled by retrograde transport of pseudorabies virus injection into autonomic ganglia?

Answer 3

PVN (hypothal). caudal raphe nuclei. rostral ventrolateral medulla. ventromedial medulla. A5 noradregergic cell group aka locus coeruleus

Question 4

baroreceptor reflex: what happens if BP increases? decreases?

Answer 4

increased BP = decreased HR, vasodilation. decreased BP = increased HR, vasoconstriction

Question 5

high blood pressure: carotid sensors? symp/parasymp response?

Answer 5

high blood pressure = increased firing of carotid sinus stretch receptors = reduced sympathetic outflow, increased parasympathetic outflow

Question 6

baroreceptor afferents: what type of input to where?

Answer 6

glutamatergic monosynaptic excitatory input to NTS neurons

Question 7

barosensitive NTS neurons initiate 2 pathways? regulation?

Answer 7

sympathoinhibitory pathway: controls total peripheral resistance. cardioinhibitory pathway: elicits rapid changes in heart rate. these two pathways are independently regulated.

Question 8

baroreflex: sympathoinhibitoy pathway: what 5 neurons?

Answer 8

baroreceptor afferents onto NTS neurons onto CVLM neurons onto RVLM neurons onto IML neurons.

Question 9

CVLM? RVLM? IML?

Answer 9

caudal ventrolateral medulla. rostral ventrolateral medulla. intermediolateral nucleus (autonomic motor ganglia)

Question 10

baroreflex sympathoinhibitory pathway: baroreceptor afferent to NTS neuron?

Answer 10

baroreceptor afferent: releases glutamate to excit NTS neuron.

Question 11

baroreflex sympathoinhibitory pathway: NTS neuron projects to? with what?

Answer 11

NTS neurons project to CVLM, release glutamate to excite them.

Question 12

baroreflex sympathoinhibitory pathway:CVLM neurons: project where? release what?

Answer 12

inhibitory, GABAergic interneurons: project and inhibit RVLM neurons

Question 13

baroreflex sympathoinhibitory pathway: RVLM neurons: project where? with what?

Answer 13

RVLM: direct excitatory glutamatergic projection to preganglionic neurons of intermediolateral cell column

Question 14

baroreflex sympathoinhibitory pathway: effect? critical for maintenance?

Answer 14

sympathetic vasoconstrictor output to muscle, mesenteric and renal blood vessels. critical for tonic maintenance + reflex control of BP

Question 15

if BP falls: what happens in the baroreflex sympathoinhibitory pathway?

Answer 15

less baroreceptor afferent signals = less NTS activity = less CVLM activity = less inhibition of RVLM = increased sympathetic outflow

Question 16

baroreflex cardioinhibitory pathway: 3 components and types of projections

Answer 16

baroreceptor afferents release glutamate to excite NTS neurons. release glutamate to excite vagal preganglionic neurons in nucleus ambiguus.

Question 17

when blood pressure falls: what happens in baroreflex cardioinhibitory pathway?

Answer 17

drive to circuit is removed = less NTS/nucleus amgiuus neuron activity = parasympathetic drive to heart is withdrawn

Question 18

baroreflex via NTS

Answer 18

AVP aka ADH (vasopressin) by magnocellular neurons of the SON + PVN of hypothalamus

Question 19

baroreceptor modulation: by exercise?

Answer 19

inputs from muscle afferents/central command located in posterior hypothalamus reset baroreflex during exercise, via GABAergic neurons in NTS

Question 20

baroreceptor modulation: stress + pain?

Answer 20

projection from periaqueductal gray matter to the NTS reset baroreflex during responses to stress and pain, mediated via local GABAergic neurons in the NTS

Question 21

chemoreceptors: detect? (2) what type of outflow?

Answer 21

detect low pH and hypercapnia, strong stimulus to increase sympathetic outflow via baroreceptor reflex