Exam II: Autonomic Nervous System Flashcards
Controls visceral functions (____)
[Autonomic Nervous System]
involuntary
Activation occurs mainly from
hypothalamus, ___ and ___
[Autonomic Nervous System]
brainstem, and spinal cord
Divisions – (3):
[Autonomic Nervous System]
Sympathetic
Parasympathetic
Enteric (GI function regulated independent from the two other divisions)
Enteric (GI function regulated___ the two other divisions)
[Autonomic Nervous System]
independent from
Activity is a balance between the first two; most target organs have innervation from both ___ and ___.
[Autonomic Nervous System]
sympathetic and parasympathetic
There is a baseline “tone” that normally keeps the vessels ___ about 50%.
[Autonomic Nervous System]
constricted
Nerves arise from ___ to ___ segments of the spinal cord
[Sympathetic]
T1 to L2
Preganglionic neurons are located in the ___ horn of the spinal cord; fibers leave with the ___ nerve roots and go into one of ___pairs of ganglia in the paravertebral sympathetic chain.
[Sympathetic]
intermediolateral, ventral, 22
Some at the same level, but most travel ___ or ___ prior to synapsing.
[Sympathetic]
cephalad or caudad
In this chain, most preganglionic sympathetic neurons synapse with cell bodies of ___fibers.
[Sympathetic]
postganglionic
Most postganglionic fibers exit the chain for the ___.
Preganglionic – mostly myelinated, fairly slow B fibers
Postganglionic – mostly unmyelinated C fibers
[Sympathetic]
target organs
Preganglionic – mostly myelinated, ___ fibers
[Sympathetic]
fairly slow B
Postganglionic – mostly unmyelinated___
[Sympathetic]
Postganglionic – mostly unmyelinated C fibers
May have some postganglionic fibers in gray rami leading to spinal nerves and traveling with these nerves to affect ___ muscle tone and the activity of ___muscles and ___.
[Sympathetic]
vascular smooth, piloerector, sweat glands
Some preganglionic fibers continue out of the ___ ___ to pass to an outlying collateral ganglion like the celiac or mesenteric ganglia.
[Sympathetic]
paravertebral chain
White ramus – ___
[Sympathetic]
myelinated
Nerves arise from cranial nerves ___, ___, ___, ___, and ____and from the sacral spinal cord
[Parasympathetic]
III, V, VII, IX, and X
Cranial ___, ___, ___, ___ – supply the head
[Parasympathetic]
III, V, VII, IX
Cranial ___(vagus) – 75% of all parasympathetic NS fibers are supplying the ___ and ___
[Parasympathetic]
X, thorax and abdomen
Sacral – ___, ___ and sometimes ___, ___ – supply the pelvis
[Parasympathetic]
S2, S3, S1, S4
Preganglionic fibers pass to ___near or in target organs
[Parasympathetic]
ganglia
Postganglionic neurons are ___, due to their proximity to the target organ (contrasting with those of ___ NS)
[Parasympathetic]
short, sympathetic
All preganglionic neurons release ___) – cholinergic fibers
[Physiology / Neurotransmitters]
acetylcholine (ACh
ACH release at preganglionic fibers activates both ___ and ___postganglionic fibers.
[Physiology / Neurotransmitters]
SNS and PNS
___ fibers and some ___fiber (sweat glands and some blood vessels) secrete Ach.
[Physiology / Neurotransmitters]
PNS postganglionic, SNS
An increase in the ___ of Ach affects both as well
[Physiology / Neurotransmitters]
availability
Sympathetic NS postganglionic fibers release ___ – called ___fibers.
[Physiology / Neurotransmitters]
norepinephrine, adrenergic
Other neurotransmitters of the ANS include ___, ___, ___, and ____.
[Physiology / Neurotransmitters]
dopamine, Vasoactive Intestinal Polypeptide (VIP), ATP, and neuropeptide Y.
Neurotransmitters are stored in ___ in nerve endings.
[Physiology / Neurotransmitters]
synaptic vesicles
Synthesized from ____ and ___ by series of enzymatic-controlled steps.
Tyrosine-dopa-dopamine-norepinephrine-epinephrine
[Norepinepherine]
phenylalanine and tyrosine
May circulate and has a slightly longer action than ___ (circulating ½ life of ___ minutes).
[Norepinepherine]
ACh, 2
Sympathetic NS postganglionic fibers release ____ – called ___ fibers.
[Norepinepherine]
norepinephrine, adrenergic
Other neurotransmitters of the ANS include dopamine, Vasoactive ___, ____, ___.
[Norepinepherine]
Intestinal Polypeptide (VIP), ATP, and neuropeptide Y
Neurotransmitters are stored in ___ vesicles in ___
[Norepinepherine]
synaptic, nerve endings
Synthesized from ___ and ___ by series of enzymatic-controlled steps
Tyrosine-dopa-dopamine-___-___
[Norepinepherine]
phenylalanine and tyrosine
norepinephrine-epinephrine
May circulate and has a slightly longer action than ___ (circulating ½ life of ___ minutes).
[Norepinepherine]
ACh, 2
Termination of action
Reuptake - ___% back into ___sympathetic nerve endings
Reusable
Can be ___ (cocaine)
[Norepinepherine]
80, postganglionic
blocked
Metabolism
Monoamine oxidase (MAO) – located intracellularly on the ___ of noradrenergic nerve endings
Catechol-O-methyltransferase (COMT) – located excellularly in many tissues, mostly in the ___.
[Norepinepherine]
mitochondria
liver
Dilution by___ from receptors
[Norepinepherine]
diffusion
Synthesized from ___ and ___ by choline acetyltransferase.
[Acetylcholine]
choline and acetyl coenzyme A
Stored in ___ vesicles
[Acetylcholine]
synaptic
Rapidly metabolized by ____to choline and acetate.
[Acetylcholine]
acetylcholinesterase
Short duration and highly ___effect
[Acetylcholine]
localized
A 2 stim: presynaptic, postsynaptic
Inhibition of norepinephrine release (___ feedback loop) - ___
[Sympathetics - Review]
negative,
presynaptic
A2 stim: presynaptic, postsynaptic
Effects the ___synaptic alpha 2 receptors in the CNS (___polarization - sedation, decreased MAC, decreased sympathetic outflow causing ___ and ___)
[Sympathetics - Review]
post, hyper, vasodilation and decreased BP
A 2 stim: presynaptic, postsynaptic
Contraction of some vascular smooth muscle (___-synaptic)
[Sympathetics - Review]
postsynaptic
A 2 stim: presynaptic, postsynaptic
Platelet aggregation (___-synaptic)
___ insulin release
[Sympathetics - Review]
Postsynaptic
Decrease
A 2 stim: presynaptic, postsynaptic
act via G protein subgroup ___, inhibiting ___ ___, reducing cyclic AMP (cAMP) and calcium levels. The net effect is ___ of the SNS response.
[Sympathetics - Review]
Gi, adenylate cyclase, downregulation
Alpha-2 receptors are largely ___ and act via G protein subgroup Gi, ___ adenylate cyclase, reducing ___ and ___
The net effect is downregulation of the SNS response.
[Sympathetics - Review]
presynaptic, inhibiting, cyclic AMP (cAMP) and calcium levels.
Beta1 stimulation – ___, located in the ___
[Sympathetics - Review]
postsynaptic, heart
Inotropic – ___
[Sympathetics - Review]
increased force of contraction
___– increased heart rate
[Sympathetics - Review]
Chronotropic
Dromotropic – ___
[Sympathetics - Review]
increased conduction
Beta receptors are also G protein linked, (protein ___), adenylate cyclase activity is___, leading to increased ____.
Stimulation initiates ___ ___ ___ reactions and stimulates sodium-potassium pump
[Sympathetics - Review]
Gs, increased, intracellular cAMP
cascading protein phosphorylation
Beta2 stimulation –___, located in ___ and ___
[Sympathetics - Review]
postsynaptic, smooth muscle and gland cells
B 2 Stim:
Relaxation of the___, ___ and vascular smooth muscles (bronchodilation, vasodilation, relaxation of the uterus, GU/GI.)
[Sympathetics - Review]
respiratory, uterine
B 2 stim:
___ of skeletal muscle vasculature
[Sympathetics - Review]
Vasodilation
B 2 stim:
Relaxation of ___ muscle of eye – far vision
[Sympathetics - Review]
ciliary
B 2 stim:
Glycogenolysis, lipolysis, gluconeogenesis, ___insulin release
[Sympathetics - Review]
increase
2nd messenger, ___ is increased
(similar to B1), but intracellular response is
___ specific (may cause different effects in
different cell types)
[Sympathetics - Review]
cAMP, tissue
Dopamine1 –___
Vasodilation of renal, ___, ___, and cerebral blood vessels
[Sympathetics - Review]
postsynaptic, mesenteric, coronary
Dopamine2 – ___
Inhibit release of ___
Nausea and vomiting
[Sympathetics - Review]
presynaptic, norepinephrine
Dopamine 1 – G protein ___ – ___ adenylate cyclase – ___cAMP
[Sympathetics - Review]
Gs, increase, increase
Dopamine 2 – G protein ___ – ___ adenylate cyclase – ___ cAMP
[Sympathetics - Review]
Gi, decrease, decrease
Cholinergic
___ –all receptors within a ANS ganglion
Also receptors at ___
[Receptor]
Nicotinic, NMJ
Muscarinic
M1 – ___ ___ and the __
[Receptor]
autonomic ganglia and the CNS
M2 – in the ___ and ___ ___
[Receptor]
principally in the heart and salivary glands
M3 – ___ ___
[Receptor]
bronchial tree
Nicotinic receptors are ____ channels – membrane proteins that form ___ ion channels.
[Receptors]
ligand-gated ion, nonselective
Muscarinic receptors are ___ protein coupled receptors – more like ___ receptors.
[Receptors]
G, adrenergic
Muscarinic ___, ___, ___ – G protein Gq – increase phospholipase C – increase ___, ___, ___
[Receptors]
1, 3, 5, IP3, DAG, Ca++
Muscarinic __, ___ – G protein Gi – ___ adenylate cyclase – ____cAMP
[Receptors]
2, 4, decrease, decrease
Innervated by ____ fibers that come directly from the ___ ___(bypassing the paravertebral ganglia)
[Adrenal Medulla]
preganglionic, spinal cord
SNS stimulation causes release of ____(80%) and ___ (20%) which act as ___ instead of neurotransmitters.
[Adrenal Medulla]
epinephrine , NE, hormones
Thus, the effects are prolonged (___ to ___seconds) and possibly stimulation of parts ___ ___ by the SNS.
[Adrenal Medulla]
10 to 30, not innervated
Preganglionic fibers
Prolonged effect reflects the time necessary for metabolism of ___, ___, and ___
[Adrenal Medulla]
E and NE by COMT.
Metabolic rate of all cells can be influenced by hormones released from the ___ ___, even those cells ___ ___ by the SNS.
[Adrenal medulla]
adrenal medulla, not innervated
