Lecture 6: Autonomic and Somatic Nervous Systems

Question 1

the nervous system is divided into ___ and ___ branches

Answer 1

central and peripheral

Question 2

the peripheral nervous system is divided into the sensory systems of ___ and ___

Answer 2

autonomic and somatic

Question 3

the autonomic nervous system is divided into ___ and ___ branches

Answer 3

sympathetic and parasympathetic

Question 4

movement, respiration, posture and voluntary movements are controlled by what branch of the peripheral nervous system?

Answer 4

somatic

Question 5

cardiac output, blood flow, digestion etc and involuntary control are controlled by what branch of the peripheral nervous system?

Answer 5

autonomic

Question 6

the ___ nervous system regulates processes in the fight/flight response

Answer 6

sympathetic

Question 7

the ___ nervous system regulates processes in the rest/digest response

Answer 7

parasympathetic

Question 8

in the sympathetic system, the ganglia cluster together in a structure called the ___

Answer 8

sympathetic chain

Question 9

location of parasympathetic ganglia

Answer 9

close to or within their target organs

Question 10

in both sympathetic and parasympathetic systems, the preganglionic neurons release ___ into the synapse with the post ganglionic cell

Answer 10

acetylcholine

Question 11

___- receptors on the post-ganglionic cells receive the signal and propagate ___ along to the target tissue

Answer 11

nicotinic Ach; action potentials

Question 12

the post-ganglionic cells of the parasympathetic nervous system release ___ and the target tissue typically express ___ type Ach receptors

Answer 12

Ach; muscarinic

Question 13

in most tissues of the sympathetic system, ___ type receptors are expressed and respond to ___ (NT)

Answer 13

adrenergic; NE

Question 14

___ are endogenous agonists

Answer 14

neurotransmitters

Question 15

controlled release of ___ transmits signals to the specific tissue that is to be activated

Answer 15

NT

Question 16

___ trigger the release of neurotransmitter

Answer 16

AP

Question 17

___ are the primary mediators of signals in many systems

Answer 17

NT

Question 18

the propagation of action potentials between neurons is carried out by ___

Answer 18

neurotransmitters

Question 19

influx of ___ion causes NT release at the synapse

Answer 19

Ca

Question 20

a ____ will be created if a stimulus / amount of NT is not great enough to trigger an AP

Answer 20

EPSP

Question 21

what are the 3 structurally related catecholamine NT?

Answer 21

NE , E , and dopamine

Question 22

epinephrine is released by the ___ in response to ___

Answer 22

adrenal gland; sympathetic activation

Question 23

t/f E and NE act on similar receptors

Answer 23

true

Question 24

which NT is the key mediator in the CNS?

Answer 24

ach

Question 25

t/f there are multiple receptor types involved in Ach signalling to generate specific responses in different tissues

Answer 25

true

Question 26

what are the 2 main classes of cholinergic receptors?

Answer 26

nicotinic and muscarinic

Question 27

what are the 2 types of nicotinic receptors? where is each type found?

Answer 27

1. Neuronal (NN): found in CNS & ANS | 2. Muscular (NM): found in neuromuscular junction

Question 28

what are the 2 families of muscarinic receptors? where is each found?

Answer 28

1. Odd (M1,3,5): found in CNS & smooth muscle | 2. Even (M2&4): found in heart & CNS

Question 29

what receptors type are nicotinic ach receptors?

Answer 29

ligand-gated ion channels

Question 30

what type of nicotinic receptors are present in the pre and ganglionic neurons of the parasympathetic nervous system?

Answer 30

neuronal

Question 31

describe the 4 steps involved in action of nicotinic receptors

Answer 31

1. ach binds, resulting in conformational change 2. influx of Na 3. change in membrane excitability (depolarization) 4. action potential or muscle contraction

Question 32

what type of receptors are muscarinic receptors?

Answer 32

GPCR

Question 33

even muscarinic receptors have ___ effects

Answer 33

excitatory

Question 34

odd muscarinic receptors have ___ effects

Answer 34

inhibitory

Question 35

M1,3,5 are ___ coupled GPCRs

Answer 35

gQ

Question 36

M2&4 are ___ coupled GPCRs

Answer 36

Gi

Question 37

the primary effects of most GI GPCRs is the decrease the cellular levels of ____, which reduces cell activities

Answer 37

cAMP

Question 38

binding of agonist to GPCR causes a ____ change and the ___ of the G-alpa and G-beta subunits

Answer 38

conformational change; dissociation

Question 39

the dissociation of the G-alpha and G-beta subunits results in the initiation of ____

Answer 39

signalling cascaded

Question 40

activation of a GQ coupled pathway in a neuronal cell would be expected to cause what result?

Answer 40

increased NT release

Question 41

activation of a GQ coupled pathway in a muscle cell would be expected to cause what result?

Answer 41

muscle contraction

Question 42

what are the 4 steps in activation of muscarinic receptors?

Answer 42

1. agonist binds to extracellular surface of receptor 2. conformational change causing the exchange of GDP for GTP on the G protein 3. Ga and Gb dissociate from the receptor and initiate intracellular signalling cascades 4. 2nd messenger molecule amplify the signal and initiate cellular response

Question 43

responses initiated by Ach are regulated by the rapid ___ in the synapse

Answer 43

Ach breakdown

Question 44

____ is a membrane-bound enzyme that cleaves Ach into inactive products, quickly terminating neuronal response

Answer 44

Ache

Question 45

Ach is made and stored in the ___ within structures called ___

Answer 45

nerve terminal; vessicless

Question 46

Ach is released in response to ___

Answer 46

AP

Question 47

in addition to binding to postsynaptic receptors, Ach also defuses back to the presynaptic cell and binds to ____ receptors that act to achieve ___

Answer 47

autoreceptors; decrease NT release to prevent overstimulation and down-regulation of postsynaptic receptor

Question 48

NE is made and stored in ___

Answer 48

sympathetic neurons

Question 49

VMAT (vesicular monoamine transporter) is required for packaging and storage of ___ in nerve terminals

Answer 49

NE

Question 50

NE is made from what amino acid? what is the intermediate product?

Answer 50

tyrosine; dopamine

Question 51

differential expression of ___ within a cell determines which catecholamine is present in highest concentration

Answer 51

enzyme

Question 52

t/f increasing the amount of one catecholamine may increase the amount of another because they are made by the same pathway

Answer 52

true

Question 53

adding dopamine to manage Parkinson's can have the unintended effect of increasing ___

Answer 53

NE

Question 54

preventing metabolism of one catecholamine may result in the increased production of other metabolites, such ___ which can have cardiovascular effects

Answer 54

tyramine

Question 55

many things about NE release are similar to that of Ach, but one key difference is that NE can be taken back up into the pre-synaptic cell by ___

Answer 55

NETs, NE transporters

Question 56

the reuptake of NE to the presynaptic cell ___ the stimulatory response

Answer 56

terminates

Question 57

NE is metabolized by 2 enzymes: ___ and ___ that produce inactive metabolites

Answer 57

COMT and MAO

Question 58

what is COMT?

Answer 58

catechol-o-methyltransferase

Question 59

what is MAO

Answer 59

monoamine oxidase

Question 60

what are the 2 isoforms of MAO?

Answer 60

MAO-A and MAO-B

Question 61

COMT is one of the enzymes that metabolizes ___ in the central and peripheral nervous systems

Answer 61

catecholamines

Question 62

MOA metabolizes ___

Answer 62

catecholamines

Question 63

COMT and MAO are targets for treating ____ conditions

Answer 63

central nervous sytem

Question 64

what are the 2 main types of adrenergic receptors?

Answer 64

1. Alpha | 2. Beta

Question 65

alpha receptors have multiple ___ within each subtype

Answer 65

isoforms

Question 66

A1 receptors are primarily found in the ___ and some in the ___

Answer 66

smooth muscle; heart

Question 67

A1 receptors are coupled to ___ G proteins and what type of cellular responses?

Answer 67

GQ; increased Ca and muscle contraction

Question 68

A2 receptors are found in the ___ and ___

Answer 68

central nervous system and sympathetic nervous system

Question 69

A2 receptors are coupled to ___ G protein which regulates the ____ from presynaptic neurons

Answer 69

Gi; amount of NT release

Question 70

B1 receptors are found in the ___

Answer 70

heart

Question 71

B2 receptors are found in the ___ , ___ and ___

Answer 71

lungs, smooth muscle /blood vessels and liver

Question 72

both b1 and b2 receptors couple to ____ G protein and result in increase in __

Answer 72

Gs; cAMP

Question 73

in the heart, increased levels of cAMP results in __

Answer 73

increased contractility

Question 74

in the lungs and other smooth muscles, cAMO results ___

Answer 74

relaxation

Question 75

what are the 2 families of dopamine receptors?

Answer 75

D1 and D2

Question 76

what dopamine receptors are in the D1 family? what is their main role and what G protein are the coupled to?

Answer 76

D1 & 5; excitatory ; Gs

Question 77

where are D1 family receptors found?

Answer 77

smooth muscle and renal vasculature

Question 78

what dopamine receptors are in the D2 family? what is their main role, and what G protein are they coupled to?

Answer 78

D2, D3, & D4; inhibitory; Gi

Question 79

where are D2 family receptors found?

Answer 79

smooth muscle and presynaptic neurons

Question 80

D2 receptors in presynaptic neurons act as ___

Answer 80

autoreceptors

Question 81

the eye is an example of a tissue that can be influenced by what branch of the ANS?

Answer 81

both parasympathetic and sympathetic

Question 82

Ach cause pupil ___

Answer 82

constriction

Question 83

NE causes pupil ___

Answer 83

dilation

Question 84

ach causes the lens to accommodate for ___ vision by becoming more ___ in shape

Answer 84

near ; round

Question 85

NE cause lens to accommodate for ___ vision by becoming more ___ in shape

Answer 85

far; flat

Question 86

intraocular pressure is determined by the balance between __ and __

Answer 86

aqueous humour secretion into the eye and aqueous outflow

Question 87

___ (NT) stimulates the secretion of aqueous humour into the eye

Answer 87

NE

Question 88

____ (NT) stimulates aqueous outflow, having a net effect of lowering intraocular pressure

Answer 88

Ach

Question 89

the dynamic sliding back and forth between sympathetic and parasympathetic is called

Answer 89

autonomic tone