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Flashcards in ANS I Deck (31):
1

What is an agonist? what is an antagonist?

1. agonist = activator
2. antagonist = inactivator

2

What do the following terms mean:
1. ionotropic
2. chronotropic
3. dromotropic

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

3

What are the sympathetic effects on the heart?

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

4

What are the PNS effects on the heart?

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

5

Which neurons are myelinated, preganglionic or postganglionic ?

preganglionic

6

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

-ACh
-binds to N1 nicotinic cholinergic receptors

7

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

-ACh
-binds to N2 nicotinic cholinergic receptors

8

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

-ACh
-muscarinic cholinergic

9

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

-Norepinephrine
-alpha or beta adrenergic

10

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

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

11

Why is sympathetic stimulation of the adrenal medulla long lasting?

The hormones released are inactivated slower

12

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

Eccrine glands - muscarinic cholinergic receptors

13

Which type of receptors are ionotropic?

Nicotinic cholinergic - N1, N2

Na+/K+ ligand gated channel

14

What is the antagonist of N1 receptors?

D-tubocurarine

15

What is the antagonist of N2 receptors ?

Hexamethonium

16

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

atropine

17

Name the following for M1, 3 ,5 receptors:
1. G protein
2. Linked Enzyme
3. Secondary messengers

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

18

Name the following for M2,4 receptors:
1. G protein
2. Linked Enzyme
3. Secondary messengers

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

19

Name the following for alpha1 adrenergic receptors:
1. G protein
2. Linked Enzyme
3. Secondary messengers

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

20

Name the following for beta adrenergic receptors:
1. G protein
2. Linked Enzyme
3. Secondary messengers

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

21

What is the antagonist of M2 , 4 receptors?

Atropine

22

What is the antagonist of B1 adrenergic receptors?

Propanolol

23

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

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

24

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

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

25

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

- Increased heart rate and force of contraction

26

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

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

27

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

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

28

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

Beta adrenergic -- heart, liver, lungs

29

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

Alpha adrenergic receptors - vasculature

30

What hormone does the adrenal medulla secrete more of?

80 % epinephrine
20% norepinephrine

31

What stimulates the conversion from norepinephrine to epinephrine?

Cortisol