ANS I

Question 1

What is an agonist? what is an antagonist?

Answer 1

1. agonist = activator

2. antagonist = inactivator

Question 2

What do the following terms mean:

1. ionotropic
2. chronotropic
3. dromotropic

Answer 2

1. ligand gated
2. affecting heart rate
3. affects AV node- conduction of speed

Question 3

What are the sympathetic effects on the heart?

Answer 3

1. stimulation of heart rate at SA node
2. stimulation of AV nodal conduction
3. stimulation of myocardial contractility

Question 4

What are the PNS effects on the heart?

Answer 4

1. Inhibition of HR at SA node
2. inhibition of AV nodal conduction
3. inhibition of atrial contractility

Question 5

Which neurons are myelinated, preganglionic or postganglionic ?

Answer 5

preganglionic

Question 6

What transmitter do somatic neurons release? and what receptor does it bind to?

Answer 6

• ACh

- binds to N1 nicotinic cholinergic receptors

Question 7

What transmitter do preganglionic ANS neurons release and what receptors does it bind to?

Answer 7

• ACh

- binds to N2 nicotinic cholinergic receptors

Question 8

What transmitter does a postganglionic parasympathetic neuron release and what receptor does it bind to?

Answer 8

• ACh

- muscarinic cholinergic

Question 9

What transmitter do postganglionic sympathetic neurons release and what receptors does it bind to?

Answer 9

• Norepinephrine

- alpha or beta adrenergic

Question 10

What neuron activates the adrenal medulla, and how is this accomplished?

Answer 10

• Sympathetic preganglionic neurons release Ach to chromaffin cells
• these cells release epinephrine (80%)

Question 11

Why is sympathetic stimulation of the adrenal medulla long lasting?

Answer 11

The hormones released are inactivated slower

Question 12

When is there an exception to the receptors the sympathetic neurons usually stimulate?

Answer 12

Eccrine glands - muscarinic cholinergic receptors

Question 13

Which type of receptors are ionotropic?

Answer 13

Nicotinic cholinergic - N1, N2

Na+/K+ ligand gated channel

Question 14

What is the antagonist of N1 receptors?

Answer 14

D-tubocurarine

Question 15

What is the antagonist of N2 receptors ?

Answer 15

Hexamethonium

Question 16

What is the antagonist of the M1,M3, M5 muscarinic receptors?

Answer 16

atropine

Question 17

Name the following for M1, 3 ,5 receptors:

1. G protein
2. Linked Enzyme
3. Secondary messengers

Answer 17

1. G alpha q
2. PLC
3. IP3 and DAG

Question 18

Name the following for M2,4 receptors:

1. G protein
2. Linked Enzyme
3. Secondary messengers

Answer 18

1. G alpha 1 and G alpha 0
2. adenylyl cyclase
3. Decreased cAMP

Question 19

Name the following for alpha1 adrenergic receptors:

1. G protein
2. Linked Enzyme
3. Secondary messengers

Answer 19

1. G alpha q
2. PLC
3. IP3 and DAG

Question 20

Name the following for beta adrenergic receptors:

1. G protein
2. Linked Enzyme
3. Secondary messengers

Answer 20

1. G alpha S
2. adenylyl cylcase
3. increased cAMP

Question 21

What is the antagonist of M2 , 4 receptors?

Answer 21

Atropine

Question 22

What is the antagonist of B1 adrenergic receptors?

Answer 22

Propanolol

Question 23

What are some of the effects of the sympathetic nervous system? (8)

Answer 23

1. Inc mydriasis and eyelid retraction
2. Inc HR and force of contraction
3. Inc bronchial dilation
4. Inc vasoconstriction (vasodilation to active muscles)
5. Inc sweating
6. Inc cell. Metabolism
7. Dec GI motility – smooth muscle walls
8. Inc contraction of sphincters

Question 24

Which sympathetic effects result from stimulation of alpha 1 receptors? (3)

Answer 24

1. Mydriasis and eyelid retraction
2. vasoconstriction
3. contraction of sphincters
   ex. receptor in the internal sphincter found in the bladder

Question 25

Which sympathetic effects result from stimulation of beta 1 receptors? (1)

Answer 25

- Increased heart rate and force of contraction

Question 26

Which sympathetic effects result from stimulation of beta 2 receptors? (2)

Answer 26

- bronchial dilation | - also on the detrusor muscle in the bladder for relaxation

Question 27

Which sympathetic effects result from stimulation of both alpha and beta receptors? (2)

Answer 27

1. decreased GI motility - smooth muscle walls | 2. increased cellular metabolism - epi from medulla

Question 28

What receptors does epinephrine have a greater affinity for? Where do these primarily exist?

Answer 28

Beta adrenergic -- heart, liver, lungs

Question 29

What does norepinephrine have a greater affinity for? Where are these primarily expressed?

Answer 29

Alpha adrenergic receptors - vasculature

Question 30

What hormone does the adrenal medulla secrete more of?

Answer 30

80 % epinephrine | 20% norepinephrine

Question 31

What stimulates the conversion from norepinephrine to epinephrine?

Answer 31

Cortisol