2: Hsf A9: Autonomic Nervous System

Front 1

1) For the sympathetic nervous system, axons from preganglionic cells are carried through which spinal nerves?
2) Where are the ganglia for the sympathetic nervous system?

Back 1

1) T1-L2
2) Either in chain of paravertebral ganglia or prevertebral ganglia in abdominal cavity (celiac, superior, inferior mesenteric)

Front 2

1) What are the celiac ganglion, superior and inferior mesenteric ganglion innervated by? What modalities are these nerves carrying?

2) Postganglionic cells from these ganglia release what neurotransmitter?

3) Preganglionic cells that synapse directly with the adrenal medulla primarily secrete what NT?

Back 2

Splanchnic nerves, all carrying sympathetic fibers EXCEPT for pelvic splanchnic nerves that carry parasympathetic fibers

2) NE.

3) Epinephrine

Front 3

1) What are catecholamines?
2) What is another name for epinephrine?
3) What are receptors for norepinephrine and epinephrine termed?

Back 3

1) Biogenic amines - dopamine, norepinephrine, epinephrine. Derived from tyrosine.
2) Adrenaline
3) Adrenergic

Front 4

1) Which cranial nerves carry preganglionic cells of the parasympathetic nervous system?
2) Are the postganglionics long?
3) Can postganglionic fibers from the sympathetic nervous system pass through parasympathetic ganglia?

Back 4

1) 3, 7, 9, 10, and sacral nerves S2-S4
2) Short - the ganglia are closely associated with the target tissue
3) Yes, so tissue receives both type of control

Front 5

1) What neurotransmitter do fibers of the somatic motor system release?

2) What neurotransmitter do preganglionic fibers of the autonomic nervous system release? What kind of receptors do they bind to?
3) What do postganglionic cells of the parasympathetic NS and sympathetic NS to the glands release? What kind of receptor does it bind to?

Back 5

1) Ach
2) Ach (cholinergic), bind to nicotinic (ionotropic) receptors. Nicotinic receptors are also stimulated by Ach release by motor neurons.
3) Ach (cholinergic) - muscarinic receptors (metabotropic)

Front 6

What neurotransmitter do postganglionic sympathetic fibers release to affect:

1) Heart/smooth muscle/glands
2) Sweat glands/some blood vessels
3) Adrenal medulla
4) What does the adrenal medulla then release?

Back 6

1) NE
2) Ach
3) Ach
4) E/NE

Front 7

1) What is acetylcholine synthesized from, and what enyzme does it?
2) What is it packaged into?
3) What is it secreted by?
4) What receptors does it bind to?
5) What is it broken down by?

Back 7

1) Acetyl coA and choline by choline acetyl transferase
2) Vesicles
3) Postganglionic cells
4) Muscarinic
5) Acetylcholinesterase

Front 8

Most postganglionic cells of the sympathetic NS are ____ and primarily release ___.

Cells of the adrenal medulla primarily secrete ___ when stimulated by Ach from preganglionic cells.

Back 8

1) Adrenergic - primarily norepinephrine
2) Epinephrine

Front 9

1) What are the actions of NE dependent upon? What are the classes?
2) Where can NE be uptaked and what degrade sit?
3) What happens when NE binds to alpha2 receptors?

Back 9

1) Receptor type - two alpha, two beta.
2) Target cell (degraded by COMT) or secreting neuron (MAO)
3) Feedbacks to inhibit synthesis and secretion

Front 10

Alpha 1 receptors:

1) Where are they located?
2) What kind of receptor is it?
3) What is the effect of the hormone binding to it?

Back 10

1) Vascular smooth muscle
2) Gq
3) Contraction of arteriolar smooth muscle. Increases blood pressure. - PIP2 -> IP3, DAG, contraction via Ca2++ release by IP3

Front 11

Alpha 2 receptors:

1) Where are they located?
2) What kind of receptor is it?
3) What is the overall effect of the hormone binding to it?

Back 11

1) Nerve cells
2) Gi
3) less cAMP, less calcium released, less nerve cell excitation, resulting in pre- and post-synaptic inhibition via cAMP. Also lowered blood pressure and pain perception

Front 12

Beta 1 receptor:

1) Where are they located?
2) What kind of receptor is it?
3) What is the overall effect of the hormone binding to it?

Back 12

1) Heart
2) Gs
3) Increased cAMP, increased heart rate and force

Front 13

Beta 2 receptors:

1) Where are they located?
2) What kind of receptor is it?
3) What is the overall oeffect of the hormone binding to it?

Back 13

1) Smooth muscle in skeletal muscle arteries, bronchi, uterus
2) Gs
3) INHIBITION via increased cAMP, decreased contraction, blood pressure, labor, bronchial constriction

Front 14

1) Multiunit smooth muscle - less finely or finely controlled? Examples?

2) Single unit smooth muscle - less finely or finely controlled? Examples?

Back 14

1) Finely controlled - iris, arterioles

2) Less finely controlled - forms a synctium - gut

Front 15

What is sympathetic stimulation mediated by?

Back 15

Circulating epinephrine or locally released norepinephrine

Front 16

Describe the effects of norepinephrine on the urinary bladder.

Back 16

1) Relaxes bladder (beta 2 receptor)
2) Constricts detrusor (smooth muscle sphincter) so bladder can fill

Front 17

The effects of IP3 and DAG (from the Gq system) can be different on different tissues. Describe their effects.

Back 17

1) DAG can activates PKC that phosphorylates proteins.

2) Ca2+ can bind to calmodulin. Combined, they activate MLCK to stimulate smooth muscle contraction

3) Ca2++ can act alone, stimulating contractile proteins associated with cell motility and secretion

Front 18

What does activation of MLCK by calcium and calmodulin (released by IP3 in Gq pathway) cause?

Back 18

Cross bridge formation in smooth muscle

Front 19

During exercise, released NE binds to which alpha receptors, and what effect does this have?

Back 19

Alpha 1 receptors - causes contraction of smooth muscle. Reduces blood flow to all tissues, but metabolites that build up (lactate, reduced pH) relaxes the smooth muscle so active, metabolizing tissues are getting the blood flow.

Front 20

What do prejunctional alpha 2 receptors on nerve terminals do?

Back 20

Inhibit NE release and cause vasodilation

Front 21

1) The alpha 2 receptor is coupled to which protein?

2) The beta 1 receptor activates what kind of G protein?

Back 21

Galpha i - decreases cAMP, less stimulation - inhibits contraction and relaxes smooth muscle by preventing release of NE

2) G protein - increases cAMP, increases contraction

Front 22

Which adrenergic receptor would you want to stimulate if you had asthma? What G protein is this coupled do, and what is the overall effect? Describe the pathway.

Back 22

Beta 2 - relaxes airway smooth muscle, and also relaxes larger arteries to supply more blood to the metabolizing tissues. Coupled to Gs protein, overall effect is INHIBITION via INCREASE in cAMP.

Stimulates increase in adenylyl cyclase, activates protein kinases to phosphorylates MLCK, which prevents calmodulin binding and activation to calcium, causing muscle relaxation.

Front 23

What is theophylline and what is it used for?

Back 23

Inhibitors of phosphodiesterase so cAMP is not broken down to AMP. Potentiates effects of epinephrine.

Front 24

What is the prominent adrenergic receptor in the heart? What is it stimulated by? What G protein is it coupled to?

Back 24

Beta 1 - stimulated by locally released NE or circulating epinephrine (which can stimulate both beta1 and beta2 receptors). Gs protein, increases cAMP, causes more heart cell contraction

Front 25

1) What receptors does isoproterenol selectively act upon?

2) What does epinephrine in a lidocaine injection act upon?

3) What does phenylephrine in over the counter cold remedies work on?

4) What does epinephrine in an inhaler or endogenous epinephrine act upon?

Back 25

1) Beta 1 and beta 2
2) Alpha 1 receptors - constricts blood flow in capillaries (lose sensation)
3) Alpha 1 receptors
4) Beta 2 receptors - dilate airway smooth muscle or large blood vessels

Front 26

What are beta 2 receptors primarily activated by? What do they do?

Back 26

Epinephrine. Relax large blood vessels to provide more blood flow.

Front 27

What do alpha 1 receptors react to? What do they do?

Back 27

Both epinephrine and norepinephrine. Constrict blood flow to arteries and capillaries to restrict blood flow to slowly metabolizing tissues.

Front 28

1) All parasympathetic responses are mediated by which kinds of receptors?
2) How does the sympathetic ns and adrenal medulla react to the heart?
3) What is the predominant receptor in the heart?
4) Blood vessels in skeletal muscle release what? What receptors does this act on, and what does it cause?
5) Do the human parotid glands do not receive what type of innervation
6) Do the sweat glands receive sympathetic innervation? What is the neurotransmitter that affects them and what are the receptors that are activated?

Back 28

1) Muscarinic
2) Sympathetic release NE, reacts with beta1 only. Adrenal medulla releases epinephrine, reacts with beta1 and beta2.
3) Beta 1.
4) Ach, muscarinic, vasodilation
5) Sympathetic
6) Yes. Ach, muscarinic.

Front 29

1) How many different types of muscarinic receptors are there that mediate parasympathetic control in different tissues?

2) What are they activated by?

Back 29

1) 5
2) Ach - mediator of parasympathetic stimulation

Front 30

What are the 5 different types of parasympathetic receptors? What is their function, and what kind of G protein are they coupled to?

Does Ach have excitatory or inhibitory effects?

Back 30

1) M1 - gastric/salivary secretion. Gq
2) M2 - Slow heart rate - Gi
3) M3 - gastric/salivary seecretion, eye accomodation, vasoconstriction. Gq
4) M4 - CNS - Gi
5) M5 - CNS - Gq

Both

Front 31

What is the effect of muscarinic stimulation on the following tissues:

1) Gut
2) Eye (antagonist?)
3) Digestive glands (agonist?)
4) Urologic

Back 31

1) Increase peristalsis, decreased sphincter tone
2) Pupil constriction, atropine
3) Salivary glands - pilocarpine
4) Relax sphinctor, increase motility of detrusor

Front 32

What is the effect of acetylocholine (parasympathetic) on:

1) Pancreatic acinar cells
2) Parotid salivary gland
3) Pancreas beta cells of islets
4) Vascular/stomach smooth muscle

Back 32

1) Secrete digestive enzymes (amylase, trypsinogen)
2) Secrete amylase
3) Secrete insulin
4) Contraction (peristalsis)

Front 33

What do alpha1 and M1, M3 receptors have in common?

Back 33

All are coupled to Gq protein, stimulates PLC to form IP3, release Ca2+, activate calmodulin and MLCK, causing contraction of smooth muscles

Front 34

1) Vasodilation is mediated by which muscarinic receptor? How does it work?

2) What is cGMP broken down by? What can inhibit this breakdown?

Back 34

1) M3 - via activation of PLC, stimulates production of NO synthase in vascular endothelial cells. NO diffuses to smooth muscle, activates guanylyl cyclase, up cGMP to promote relaxation of smooth muscle and dilation to increase blood flow.

2) Phosphodiesterase-5. Viagra, silendafil

Front 35

What happens when acetylcholine interacts with the heart?

Back 35

Activates G protein, which activates K+ channel. K+ leaves cell, hyperpolarizes it more, slows heart rate.