ANS Receptors and Drug Targets

Question 1

M1 receptor mechanism

Answer 1

Gq protein - STIMULATORY

activate PLC –> convert PIP2 –> IP3 + DAG –> increase Ca2+

Question 2

M1 receptor locations

Answer 2

brain, salivary glands

Question 3

M1 receptor effects

Answer 3

increase secretions

Question 4

M2 receptor mechanism

Answer 4

Gi protein - INHIBITORY

inhibit AC –> decrease cAMP

Question 5

M2 receptor locations

Answer 5

heart
lugns
smooth muscle
presynaptic neurons

Question 6

M2 receptor effects

Answer 6

decrease HR/contractility
bronchoconstriction
smooth muscle contraction
autoinhibition of synapses

Question 7

M3 receptor mechanism

Answer 7

Gq protein - STIMULATORY

activate PLC –> convert PIP2 –> IP3 + DAG –> increase Ca2+

Question 8

M3 receptor locations

Answer 8

pupils
detrusor muscle
lungs

Question 9

M3 receptor effects

Answer 9

miosis
detrusor contraction –> urine release
bronchoconstriction

Question 10

a1 receptor mechanism

Answer 10

Gq protein - STIMULATORY

activate PLC –> convert PIP2 –> IP3 + DAG –> increase Ca2+

Question 11

a1 receptor locations

Answer 11

blood vessels
pupils
smooth muscle
internal urethral sphincter
CNS

Question 12

a1 receptor effects

Answer 12

vasoconstriction
hypertension
mydriasis
smooth muscle contraction
internal urethral sphincter contration –> urinary retention
increased alertness/excitement

Question 13

a2 receptor mechanism

Answer 13

Gi protein - INHIBITORY

inhibit AC –> decrease cAMP

Question 14

a2 receptor locations

Answer 14

presynaptic neurons
CNS (locus coeruleus)
heart
blood vessels
endocrine

Question 15

a2 receptor effects

Answer 15

autoinhibition of synapses

a2 agonists:
sedation, amnesia, analgesia, muscle relaxation
decrease HR
high dose: vasoconstriction/hypertension
low dose: vasodilation/hypotension
inhibit ADH –> increased urination
inhibit insulin –> hyperglycemia

Question 16

B receptor mechanism

Answer 16

Gs protein - STIMULATORY

stimulate AC –> increase cAMP

Question 17

B1 receptor locations

Answer 17

heart

Question 18

B1 receptor effects

Answer 18

increase HR and contractility

Question 19

B2 receptor location

Answer 19

blood vessels
lungs
smooth muscle

Question 20

B2 receptor effects

Answer 20

vasodilation/hypotension
bronchodilation
smooth muscle relaxation

Question 21

B3 receptor location

Answer 21

detrusor muscle

Question 22

B3 receptor effects

Answer 22

detrusor muscle relaxation –> urinary retention

Question 23

D1 receptor mechanism

Answer 23

Gs protein - STIMULATORY

stimulate AC –> increase cAMP

Question 24

D1 receptor location

Answer 24

blood vessels

Question 25

D1 receptor effects

Answer 25

vasodilation increases blood flow

Question 26

D2 receptor mechanism

Answer 26

Gi protein - INHIBITORY inhibit AC --> decrease cAMP

Question 27

D2 receptor location

Answer 27

CNS CRTZ

Question 28

D2 receptor effects

Answer 28

emesis induce anxiety and fear

Question 29

u/k opioid mechanism

Answer 29

Gi protein - INHIBITORY inhibit AC --> decrease cAMP

Question 30

u/k opioid location

Answer 30

periphery/spinal cord interneurons CNS respiratory centers GI

Question 31

u/k opioid effects

Answer 31

analgesia sedation (dogs) euphoria (cats, low dose) excitement (cats/horses, high dose) hypoventilation decreased peristalsis

Question 32

benzodiazepine mechanism

Answer 32

binds y subunit of GABAa receptor opens Cl- pore to hyperpolarize cell

Question 33

benzodiazepine locations

Answer 33

CNS hippocampus skeletal muscle

Question 34

benzodiazepine effects

Answer 34

sedation (sheep, goats, cattle, pigs) excitement (dogs, cats, horses) anticonvulsant amnesia muscle relaxation

Question 35

anesthetic GABAa mechanism

Answer 35

binds to a or b subunit

Question 36

anesthetic GABAa locations

Answer 36

CNS hippocampus skeletal muscle respiratory

Question 37

anesthetic GABAa effects

Answer 37

anesthesia hypoventilation sedation (sheep, goats, cattle, pigs) excitement (dogs, cats, horses) anticonvulsant amnesia muscle relaxation

Question 38

NMDA receptor mechanism

Answer 38

binds to glutamate receptor to open cation pore to depolarize cell

Question 39

NMDA receptor locations

Answer 39

CNS hippocampus periphery & spinal cord skeletal muscle

Question 40

NMDA receptor effects

Answer 40

mediates pathways between brainstem and cortex memory formation modulates pain pathways inhibits UMNs of skeletal muscle