Autonomic Nervous System Neurotransmitters

Question 1

What are the 3 neurotransmitters are released by autonomic neurons

Answer 1

Acetylcholine (Ach) and Norepinephrine (NE)

Question 2

What parts of the ANS are cholinergic neurons

Answer 2

all preganglionic neurons of the sympathetic and parasympathetic divisions, the post ganglionic neurons of the parasympathetic and the post sympathetic neurons of the sympathetic division that go to sweat glands

Question 3

What parts of the ANS are adrenergic neurons

Answer 3

all post ganglionic neurons of the sympathetic division except the nerve that innervate sweat glands

Question 4

What are the 2 types of cholinergic receptors and what are they named after

Answer 4

Nicotinic- nicotine mimics Ach at these receptors

Muscarinic– muscarine (a mushroom poison) mimics Ach at these receptors

Question 5

Is there cross reactivity of nicotine or muscarine receptors

Answer 5

no

Question 6

Are the effects of Ach long lasting or short acting and why

Answer 6

The effects of Ach are quick b/c acetylcholinesterase quickly deactivates AcH

Question 7

What is the effect of Ach on nicotinic receptors

Answer 7

depolarization

Question 8

What is the effect of Ach on muscarine receptors

Answer 8

depolarization or hyperpolarization it depends on the post synaptic cells

Question 9

What is the Mnemonic that helps you remember what muscarine receptors causes

Answer 9

DUMBELS

defecation
urination
miosis (eye contraction)
bronchoconstriction
emesis
lacrimation
sweating

Question 10

True or false epinephrine is they only neurotransmitter released by the sympathetic postganglionic neurons

Answer 10

False, NE is released by most sympathetic neurons except for those that go to sweat glands (these release Ach)

Question 11

What are the types of adrenergic receptors

Answer 11

alpha 1 and 2

beta 1, 2, and 3

Question 12

What does activation of adrenergic receptors with the subscript 1 typically do

Answer 12

depolarize (excite)

Question 13

What does activation of adrenergic receptors with the subscript 2 typically do

Answer 13

hyperpolarize (inhibit)

Question 14

What does activation of adrenergic receptors with the subscript 3 typically do

Answer 14

only to brown adipose tissue so it causes thermogenesis

Question 15

Why do adrenergic effects last longer than cholinergic effects

Answer 15

NE lingers longer in the synaptic cleft when compared to Ach

Question 16

What 2 enzymes breakdown NE in the synaptic cleft

Answer 16

monoamine oxidase or catechol-o-methyltransferase

Question 17

What is an agonist

Answer 17

substance that binds to a receptor and triggers a response

Question 18

What is an antagonist

Answer 18

substance that binds to a receptor, fails to cause a response and blocks activation by agonist

Question 19

What is a partial agonist

Answer 19

substance that binds to a receptor and triggers a partial response

Question 20

What are beta blockers and what do we use them in the medical field for

Answer 20

Blocks the effect of NE/EP on the beta 1 receptors.

Since Beta 1 receptors are located primarily in the the heart it slows down heart rate

Question 21

What are alpha blockers and what do we use them in the medical field for

Answer 21

Blocks the effect of NE/EP on the alpha 1 receptors.

Since alpha 1 receptors are located in all blood vessels it lowers BP by causing vessels to relax

Question 22

What is Atropine and how do we use it in the medical field

Answer 22

Anticholinergic drug that block parasympathetic effects

Used preop to reduce secretions. to dilute pupils for eye exams, used as an antidote for chemical warfare agents that inactive acetylcholinesterase

Question 23

What is Neostigmine and what do we use it for

Answer 23

acetylcholinesterase inhibitor preventing Ach breakdown

-used to treat myasthenia gravis (dz were ach stimulation is impaired)

Question 24

How do tricyclic antidepressants work

Answer 24

prolong NE in neural synapses

-NE is a feel good drug

Question 25

How do monoamine oxidase inhibitors work and what do we use them for

Answer 25

inactvates MOA which allows NE to stay longer in synaptic cleft

used for depression