Chapter 15 Flashcards
Somatic vs autonomic NS (excitatory, voluntary, consciously perceived, function when damaged)
Somatic: when SMN stimulates SM=always excitatory, usually voluntary, usually consciously perceived
Autonomic: exciting/inhibiting to cardiac/smooth/glands, function to some extent if nerve damaged, usually not voluntary, not consciously perceived
ANS divisions
Sympathetic NS
Parasympathetic NS
Enteric NS: chemical changes/wall stretching/contraction/secretion of GI tract
Does the Somatic or autonomic NS have more motor neurons
Autonomic usually has 2+
Somatic has only one from CNS to effector
Where does preganglionic neuron extend to and is it myelinated
Myelinated
To autonomic ganglion
Or to chromaffin cells in adrenal medullae
Differences between sympathetic and parasympathetic neurons (length/release)
Sympathetic: preganglion=shorter postganglionic release NE (if chromaffin cell, also release epinephrine)
Parasympathetic: preganglionic=longer postganglion release ACh
Preganglionic axon type vs postganglionic
Pre: small diameter myelinated B fiber
Post: small diamter unmyelinated C fiber
Sympathetic AKA and why
Thoracolumbar as preG have cell bodies in lat horns of gray matter in 12 thoracic segments and first 2-3 lumbar segments
Thoracolumbar outflow
Axons of sympathetic preganglionic neurons
Parasympathetic AKA and why
Craniosacral as cell bodies of preG are in nuclei of III, VII, IX, X and in lat gray of 2 through 4 sacral segments of SC
Craniosacral outflow
Axons of parasympathetic preG neurons
Somatic vs autonomic sensory input
Somatic: somatic/special sense
A: mainly interoceptors some somatic/special
Somatic vs autonomic control of motor output
S: voluntary from CC, some basal ganglia cerebellum brainstem SC
A: involuntary from hypothalamus limbic system brainstem SC some CC
Somatic vs autonomic motor neuron pathway
S: one neuron to effector
A: 2 neuron synapse with posts in autonomic ganglia or chromaffin cells in adrenal medullae
Somatic vs autonomic NT/hormones
S: ACH
A: all preG/psymp post=ACh,
symp postG/=NE (if sweat gland=ACh)
Chromaffin: NE/epinephrine
Sympathetic trunk ganglia
Sympathetic
In vert row on either side of VC
Innervate above diaphragm
Prevertebral ganglia
Sympathetic
Ant to VC close to large abdominal arteries
Innervate below diaphragm
Terminal ganglia
Parasympathetic
Close to or within visceral organ
Superior mesenteric plexus supplies
SI/LI
Inferior mesenteric plexus supplies
LI
Hypogastric plexus supplies
Pelvic viscera
Superior cervical ganglion serve
Head and heart
Middle/inferior cervical ganglion serve
Heart and BV of neck shoulder and upper limb
Pathways from symp trunk ganglia to visceral effectors (4)
Enter spinal nerves
Form cephalic periarterial nerves
Form sympathetic nerves
Form splanchnic nerves
Gray rami communicates vs white rami communicantes (what/where)
Gray: structures containing sympathetic postG axons that connect ganglia of sympathetic trunk to spinal nerves (all 31 nerves of SC)
White: structure containing sympathetic preG axons that connect anterior ramus of spinal nerve with ganglia of sympathetic trunk (only thoracic and first 2/3 lumbar nerves)
Spinal nerves Innervate
Visceral effectors in skin of neck trunk and limbs
Cephalic periarterial nerves Innervate
Visceral effectors in skin of face and visceral effectors of head
Sympathetic nerves Innervate (what/where are they synapsing with postG)
Heart: synapse with postG in sup/middle/inf cervical ganglia and T1-T4
Lungs: synapse with postG in T2-T4
Splanchnic nerves Innervate (what/where do synapse with postG)
Abdominopelvic organs: prevertebral ganglia
Adrenal medulla: chromaffin cells
Chromaffin cels release (%)
80 percent epinephrine
20 percent NE
Trace amount dopamine
Four pairs of cranial psymp ganglia
Ciliary (eyeball)
pterygopalatine (nasal mucosa/palate/pharynx/lacrimal glands)
submandibular (submandibular/sublingual salivary glands)
otic (parotid salivary glands)
What nerve carries 80 percent of total Craniosacral outflow (psymp)
Vagus (X)
Cholinergic receptors
Nicotinic
Muscarinic
Nicotinic (locations/effects) (3)
PM of postG symp/psymp N: excitation=impulses in postG
Chromaffin cells: E/NE secretion
Sarcolemma of SMF: excitation=contraction
Muscarinic (locations/effects)(3)
Effectors innervated by psymp postG N: excitation or inhibition
Sweat glands innervated by symp postG= increased sweating
SM BV innervated by symp postG: inhibition=relaxation=vasodilation
Is NE or E both a NT and hormone
NE
Adrenergic receptors
a1, a2, B1, B2, B3
a1 (locations/effects) (3)
Smooth muscle in BV, radial muscle in iris, spinster of stomach/bladder: excitation=vasoconstriction/dilation/closing
Salivary gland cells: K+/H2O secretion
Sweat glands on palms/soles: increased sweating
a2 (locations/effects)(4)
Smooth muscle in BV: vasodilation
Beta cells of pancreatic islets: decreased insulin secretion
Pancreatic acinar cells: inhibition of digestive enzyme secretion
Platelets in blood: form platelet plug
B1 (location/effects)(4)
Cardiac MF: excitation
Juxtaglomerular cells of kidneys: renin secretion
Post pituitary: ADH secretion
Adipose cells: breakdown triglycerides=release fatty acids to blood
B2 (locations/effects(3)
Smooth muscle in airways; heart BV, SM, adipose, liver, visceral organ walls: inhibition
Ciliary muscle in eye: inhibition
Hepatocytes in liver: glycogenolysis
B3 (location/effect)(1)
Brown adipose tissue: thermogenesis
Adrenergic receptors generally excitatory
a1, B1
Adrenergic receptors generally inhibitory
a2, B2
Autonomic tone regulated by
Hypothalamus
Symp vs psymp associated ganglia
Symp: symp trunk ganglia, prevertebral ganglia
Psymp: terminal ganglia
Symp vs psymp ganglia locations
S: close to CNS
P: close to or within wall of effectors
Symp vs p symp axon divergence (postG/effector)
S: synapse with many postG to many effectors
P: synapse with 4-5 postG to single effector
Does symp or psymp have white/gray rami communicantes
Symp
Symp vs psymp NT
S: preG=ACh, post=NE (except sweat glands is ACh)
P: both ACh
What is the major control and integration center of ANS
Hypothalamus
What parts of hypothalamus control symp vs psymp
Symp: posterior and lateral hypothalamus
Psymp: anterior and medial hypothalamus
