Nicotinic and Muscarinic Receptors

Question 1

Muscarninc M1: Location (2)Responses (for each location)

Answer 1

CNS Autonomic ganglia Late EPSP (excitatory postsynaptic potential) ; complex at least arousal, attention analgesia

Question 2

Muscarninc M1: MechanismPrototype agonist/antagonist

Answer 2

Gq/11 –> PLC –> IP3 + DAG –> Ca + PKC (all increase in concentration) Oxotremorine / Pirenzepine

Question 3

Muscarininc M2: Location (4) Responses

Answer 3

All heart SA node : slowed spontaneus depolarization, hyperpolarzationAV node : decrease conduction velocity Atrium : decreased refactory period : decreased contractile forceVentricle : slight decrease in contractility

Question 4

Muscarninc M2: Mechanism Prototype agonist/antagonist

Answer 4

betagamma subunit of G Protein –> inhibits Adenylyl cyclase and increases potassium channel openingnone/ AF-DX117

Question 5

Muscarinic M3: Location (1) ResponseMechanismAntagonist

Answer 5

smooth muscle contraction same as M1hexahydrosiladifenidol

Question 6

Muscarninc M4/5LocationMechanism (2) Antagonist for M4

Answer 6

CNSM4–> M2 and M5 –> M1Himbacine antagonizes M4

Question 7

Nicotinic Nm: Locations Response

Answer 7

Skeletal muscle at NMJEnd -plate depolarization; skeletal muscle contraction

Question 8

Nicotinic Nm: MechanimAgonist/ antagonist

Answer 8

opening of Na/K channels Phenyltrimethylammonium / Tubocurare

Question 9

Nicotininc Nn : Location (3) Responses ( for each loc. )

Answer 9

Autonomic Gnglia : deplarization and firing of postganglionic neuronadrenal medulla : release of catecholaminesCNS : complex, arousal , attention, analgesia

Question 10

Nicotinic Nn:MechanismAgonist/Antagonist

Answer 10

opening of Na/K channel Dimethylphenylpiperazinium / Trimethaphan