Lecture 7 & 8 - Cholinergic Transmission

Question 1

What is part of the autonomic nervous system

Answer 1

Sympathetic
Parasympathetic
Enteric

Question 1

What does the autonomic nervous system do

Answer 1

Takes all outputs from CNS and transfers them to the rest of the body

Question 2

What does the autonomic nervous not do

Answer 2

Motor signals

Question 3

Is autonomic nervous system voluntary/involuntary

Answer 3

Involuntary

Question 4

What are the two main neurotransmitters

Answer 4

Acetylcholine (Ach)
Noradrenaline (NA)

Question 5

What does the autonomic nervous system

Answer 5

• Heartbeat
• Contraction/Relaxation of blood vessels
• Exocrine/Endocrine secretion
• Energy Metabolism

Question 6

Sympathetic Activity

Answer 6

Increases Stress (Fight/Flight)

Question 7

Parasympathetic Activity

Answer 7

Relaxation and After Meals

Question 8

All preganglionic autonomic nerve fibres release _______ that act on ______

Answer 8

Ach that acts on nicotinic receptor

Question 9

Most Postganglionic Sympathetic fibres release _____ that act on

Answer 9

NA that acts on alpha and beta adrenoceptors

Question 10

Postganglionic Sympathetic fibres
(Exceptions)

Answer 10

Sweat and Adrenal

Question 11

Sweat Glands receive signals from _____ acting on ______ receptors

Answer 11

Ach acting on Mus receptors

Question 12

Adrenal Glands receive signals from _____ acting on ______ receptors

Answer 12

Ach acting on Nic receptors

Question 13

All postganglionic Parasympathetic Fibres release _____ that act on ______

Answer 13

Ach that act on Mus receptors

Question 14

Where does Cholinergic Transmission act

Answer 14

Sympathetic, Parasympathetic, Enteric

Skeletal + CNS

Question 15

What are the two types of Ach receptors

Answer 15

Nicotinic Receptors
Muscarinic Receptors

Question 16

What kind of receptors are Nicotinic Receptors

Answer 16

Ligand-Gated Ion Channel that conduct mainly Na+

Question 17

What are the three types of Nicotinic Receptors

Answer 17

Ganglionic: Autonomic, postsynaptic
Muscle: Skeletal, postsynaptic
CNS: Brain Regions, pre- and postsynpatic

Question 18

What are the M1 and M2 and M3
(Excitatory/Inhibitory)

Answer 18

M1 = Excitatory (Gq)
M3 = Excitatory (Gq)

M2 = Inhibitory (Gi)

Question 19

M1 Receptors

Answer 19

Slow Excitation of Ganglia

Question 20

M2 Receptors

Answer 20

Decreases Cardiac rate and Contraction force

Question 21

M3 Receptors

Answer 21

Causes Gland Secretion
Contracts smooth muscle around organs (Visceral Muscle)
Vascular relaxation (NO-mediated)

Question 22

Nicotinic vs Muscarinic (Time Scale)

Answer 22

Nicotinic takes milliseconds

Muscarinic takes seconds

Question 23

What kind of effect does Cholinergics have at the Neuromuscular Junction

Answer 23

Ach binds nAchR
Causes neuromuscular blocks to relaxes muscles

Question 24

Mechanism that drugs use to produces neuromuscular blocks

Answer 24

Antagonizes nAChr through competition (non-depolarizes) Agonists that activate nAChR (depolarizes)

Question 25

Non-depolarizing Agents mechanism

Answer 25

Competitive antagonists at motor endplate nAChR Inhibits ACh release for any continuous stimuli Muscle Paralysis

Question 26

Depolarizing Agents mechanism

Answer 26

Agonist at nAChR Persistent depolarization from agonist continuously binding resistant to acetylcholinesterase Initial muscle contraction followed by paralysis

Question 27

Two types of Cholinesterases

Answer 27

Acetylcholinesterase (Synapse) Butyrylcholinesterase (Plasma)

Question 28

Uses of Anticholinesterases

Answer 28

Reverses non-depolarizing neuromuscular block Treat myasthenia gravis (weakening of bone)

Question 29

Anticholinesterase at NMJ

Answer 29

Increases muscle tension

Question 30

Anticholinesterase at CNS

Answer 30

Excitation (mAChR) followed by depression of activity - unconsciousness, respiratory failure

Question 31

How to reverse anticholinesterase depression

Answer 31

Atropine and Pralidoxime