Physiology: Autonomic Nervous System

Front 1

What is the somatic nervous system?

Back 1

Voluntary motor system under conscious control.

Front 2

What is the autonomic nervous system?

Back 2

Involuntary system controlling and modulating the functions of visceral organs.

Front 3

All preganglionic ANS neurons release which neurotransmitter?

Back 3

ACh.

Front 4

Postganglionic ANS neurons release which neurotransmitter(s)?

Back 4

ACh or norepinephrine

Front 5

What are the two main divisions of the ANS?

Back 5

Sympathetic and parasympathetic divisions.

Front 6

What is the name of the nervous system in the GI tract?

Back 6

The enteric nervous system.

Front 7

Where do the sympathetic preganglionic neurons originate from?

Back 7

The thoracolumbar spinal cord.

Front 8

From where do the parasympathetic neurons originate?

Back 8

The brain stem and sacral spinal cord.

Front 9

All postganglionic parasympathetic neurons release which neurotransmiter?

Back 9

ACh

Front 10

What type of receptors are present in the parasympathetic division targets, the smooth muscle and glands?

Back 10

Muscarinic receptors.

Front 11

What type of receptors are in the first synapse throughout the autonomic nervous system?

Back 11

Nicotinic receptors.

Front 12

What type of receptors are present in the sympathetic division targets smooth muscle and glands?

Back 12

alpha 1,2 and beta 1,2

Front 13

Which neurotransmitter is released in the second synapse at smooth muscle and glands in the sympathetic division?

Back 13

Norepinephrine.

Front 14

Which neurotransmitter is released in the second synapse at the sweat glands in the sympathetic division?

Back 14

ACh

Front 15

What type of receptor is present at the sweat glands in the sympathetic division?

Back 15

Muscarinic receptors.

Front 16

What do adrenergic neurons release?

Back 16

Norepinephrine.

Front 17

What is the substrate for adrenoreceptors?

Back 17

Norepinephrine.

Front 18

Can adrenoreceptors be activated by epinephrine?

Back 18

Yes.

Front 19

What do cholinergic neurons release?:

Back 19

ACh.

Front 20

What is the substrate for cholinoreceptors?

Back 20

ACh.

Front 21

What are the spinal segments from which the sympathetic preganglionic neurons originate?

Back 21

T1 to L3.

Front 22

What is the adrenal medulla?

Back 22

A specialized sympathetic ganglion whose preganglionic neurons originate in the thoracic spinal cord (T5-T9).

Front 23

What type of receptors are located on the adrenal medulla?

Back 23

Nicotinic receptors.

Front 24

What type of neuron synapses on the adrenal medulla?

Back 24

Cholinergic neurons.

Front 25

What type of neurotransmitters are released by the adrenal medulla?

Back 25

80% epinephrine and 20% norepinephrine.

Front 26

What are chromaffin cells?

Back 26

The target cells on the adrenal medulla which release catecholamines into the general circulation.

Front 27

What are catecholamines?

Back 27

Norepinephrine and epinephrine.

Front 28

What are the cranial nerves from which the parasympathetic division originates?

Back 28

Cranial nerves 3, 7, 9, 10.

Front 29

From which sacral cord segments does the parasympathetic division originate?

Back 29

S2 to S4.

Front 30

Where are the ganglia of the parasympathetic division located?

Back 30

Near, on or in the effector organs.

Front 31

What happens to the pupil when the radial muscle of the iris contracts?

Back 31

Dilation or mydriasis.

Front 32

What happens to the pupil when the circular muscle of the iris contracts?

Back 32

Constriction or miosis.

Front 33

What type of sympathetic receptors does the heart have?

Back 33

beta 1

Front 34

What type of parasympathetic receptors does the heart have?

Back 34

Muscarinic receptors.

Front 35

What is the effect of stimulating the beta1 receptors of the heart?

Back 35

Increased SA node (heart rate), AV nodal conduction, and contractility.

Front 36

What type of sympathetic receptors are located in the bronchioles?

Back 36

beta 2 - stimulation leads to dilation

Front 37

Where in the vasculature are alpha 1 receptors located?

Back 37

The skin, splanchnic circulation, and skeletal muscle.

Front 38

What 2 sympathetic receptor types are located in the skeletal muscle?

Back 38

alpha 1 and beta 2

Front 39

What is the mechanism of action of alpha1 adrenoreceptors?

Back 39

Increased Ca++ by coupling to DAG and IP3 - generally leads to contraction.

Front 40

Where are alpha1 adrenoreceptors located?

Back 40

1. vascular smooth muscle (skin, renal, splanchnic); 2. GI tract (sphincters); 3. bladder (sphincter); 4. radial muscle of iris.

Front 41

Where are alpha2 receptors located?

Back 41

1. GI tract (wall); 2. presynaptic adrenergic neurons.

Front 42

What is the mechanism of action of alpha2 adrenoreceptors?

Back 42

Inhibit adenylyl cyclase, decrease cAMP.

Front 43

Where are beta1 receptors located?

Back 43

1. heart; 2. salivary glands; 3. adipose tissue; 4. kidney.

Front 44

Where are beta2 receptors located?

Back 44

1. vascular smooth muscle of skeletal muscle; 2. GI tract (wall); 3. bladder (wall); 4. bronchioles.

Front 45

What is the mechanism of action of beta1 and beta2 receptors?

Back 45

stimulate adenylyl cyclase, increase cAMP.

Front 46

Where are muscarinic cholinergic receptors located?

Back 46

All PNS effector organs and the SNS sweat glands.

Front 47

Where are nicotinic cholinergic receptors located?

Back 47

Skeletal muscle (motor end plate); postganglionic neurons of the SNS and the PNS; adrenal medulla.

Front 48

What is the mechanism of action of muscarinic receptors?

Back 48

Increased Ca++ by coupling to DAG and IP3.

Front 49

What is the mechanism of action of nicotinic receptors?

Back 49

Opening of Na+ and K+ channels leading to depolarization.