functional organization

Question 1

symapthetic nerves receive what info from where? via?

Answer 1

afferent info from the targets they innervate. via spinal, supraspinal, local reflexes.

Question 2

general principle: correlation between positions of neurons and target?

Answer 2

correlation between rostrocaudal position of spinal preganglionic neurons and rostrocaudal position of target

Question 3

general principle: specificity?

Answer 3

specific groups of cells in autonomic ganglia project to specific peripheral targets

Question 4

general principle: individual ganglion cells receive what inputs?

Answer 4

one dominant input from one spinal segment, and other weaker subthreshold inputs from about four adjacent segments

Question 5

general principle: nuclei in where connect to what for what main effect

Answer 5

nuclei in medulla/brainstem/hypothalamus connect to all sympathetic ganglia via sympathetic preganglionic neurons in nuclei in the intermediolateral cell column of the spinal cord = enables coordinated discharge of symp NS

Question 6

general principle: certain nuclei from where connect to? why?

Answer 6

certain nuclei in medulla/brainstem/hypothalamus have connections to specific peripheral ganglia to enable localized and directed sympathetic discharge

Question 7

sympathetic vs para: what spinal segments

Answer 7

symapthetic = thoracic and lumbaer. para = cranial and sacral

Question 8

symp vs. para: size of pre/post ganglions

Answer 8

sympathetic: short preganglionic, long post. para = long pre, short post because ganglia close to targets

Question 9

two main places where symp ganglia found

Answer 9

paravetebral sympathetic ganglia, prevertebral symapthetic ganglia

Question 10

sympathetic: preganglionic neurons in where? (3)

Answer 10

thoracic and lumbar spinal cord: in lateral horn aka IML or intermediolateral cell column, central autonomic nucleus, and intercalated nucleus

Question 11

preganglion neurons: receptors?

Answer 11

high ratio of NMDA to kainate/AMPA receptors

Question 12

preganglionic sympathetic: axons synpase onto what 3 places

Answer 12

one or more ganglion cells in one or more paravertebral sympathetic ganglia. pass through paravertebral, synpse in ganglion cells in prevertebral sympathetic ganglia. pass through paravetebral then synapse in chromaffin cells in the adrenal medulla and SIF cells in ganglia.

Question 13

chromaffin cells: ratio of NA:A? also contain?

Answer 13

NA:A 30: 70. also contain enkephalin, NPY, somatostatin, neurotensin, GABA

Question 14

NA and A chromaffin cells may be innervated by? adrenaline/NA release triggered by what two things?

Answer 14

innervated by different groups of spinal preganglionic neurons. adrenaline: hypoglycemia. NA: fall in BP

Question 15

sympathetic ganglion cells/post ganglionic nerves release NA except in what 2 places? what do they have instead

Answer 15

muscarinic cholinergic sympathetic fibers: in eccrine (thermoregulatory) sweat glands. blood vessels within skeletal muscle (cats and dogs, not humans)

Question 16

eccrine glands as ooposed to?

Answer 16

eccrine = thermoregulatory. as opposed to apocrine glands innervated by noradrenergic sympathetic nerves.

Question 17

paravertebral sympathetic ganglia

Answer 17

superior and inferior cervical ganglion. stellate ganglion. thoracic, lumbar and sacral ganglia.

Question 18

prevertebral/preaortic ganglia include:

Answer 18

celiac ganglia. superior mesenteric ganglia (solar plexus). inferior mesenteric aka hypogastric ganglion

Question 19

ganglia of the pelvic plexus aka ? includes?

Answer 19

previsceral or terminal ganglia. mixed sympathetic and parasympathetic ganglia + short adrenergic neurons

Question 20

visceral afferents: 3 roles

Answer 20

activate autonomic reflexes. convey visceral sensation to CNS. neurogenic inflammation

Question 21

visceral afferents: local axon reflexes involving what propagation

Answer 21

antidromic propagation (aka backwards)

Question 22

triple response of Lewis (ex to what?) involves what 3 things

Answer 22

ex to insect bite: localized red spot. brighter red flush or flare develops more slowly. wheal that replaces red spot (edema)

Question 23

triple response of Lewis: flare is due to?

Answer 23

stimulation of sensory nerves by histamine produces release of substance P, CGRP, ATP

Question 24

triple response of Lewis: flare produces what 4 things, aka what

Answer 24

neurogenic inflammation / axon reflex: vasodilation, plasma protein extravasation, mast cell degradnulation, lymphocyte granulocyte macrophage activation

Question 25

pseudorabies virus: what happens to it and why use it

Answer 25

tracing experiments: because it is retrogradely transported across synapses

Question 26

what was found from pseudorabies studies

Answer 26

suprising common set of central pathways seem to influence spinal sympathetic outflow

Question 27

inject speudorabies virus into where or where will cause what same result

Answer 27

inject viurs into paraverebral (stellate or superior cervical) ganglia, or into a prevertebral ganlion, on into adrenal gland you get labeling in same five brain areas

Question 28

pseudorabies labeling: what same five brain areas

Answer 28

caudal raphe nuclei. rostral ventrolateral medulla. paraventricular nucleus (hypothlamaus). ventromedial medulla. locus coeruleus - A5 noradrenergic group

Question 29

how to prove symp NS set up for coordinate and localized/directed discharge

Answer 29

rabies tracing. localized directed discharge: other brain areas are only backlabeled from specific ganglia.

Question 30

higher level reflexes via NTS project out via? so what?

Answer 30

via ventromedial medulla = these reflexes operate below the level of consciousness

Question 31

parasymp pregnanglionic neurons found where?

Answer 31

sacral spinal cord. intermediolateral cell column aka IML aka lateral horn

Question 32

parasymp: 4 important nuclei

Answer 32

dorsal motor nucleus of vagus. nucleus ambiggus. edinger westphal nucleus. salivatory nucleus.

Question 33

cranial nerve outflow (parasymp) via what 4?

Answer 33

III: oculomotor. VII: facial. IX: glossopharyneal. X: vagus. 3, 7, 9, 10.

Question 34

parasymp: brainstem nuclei receive inputs via? vagus is mostly?

Answer 34

via NTS, baroreceptor. vagus is 80% visceral afferent fibers!

Question 35

2 components of vagal system and nuclei

Answer 35

phylogenetically older DORSAL vagal complex for control of subdiaphragmatic organs like bladder, guts - originates in dorsal motor nucleus of the vagus. phylogenetically newer VENTRAL = controls heart and facial structures, originates in nucleus ambiguus.

Question 36

summary: sympathetic vs. parasympathetic

Answer 36

sym: diffuse but highly regulated, capable of directed outflow as well as flight or fight. parasymp = much more directed. its the organization of these two systems that allows them to function in these ways