Lecture 5 and 6

Question 1

How do nerve signals travel between enurons?

Answer 1

Electrical (fast) and chemical (slow, requires neurotransmitters)

Question 2

What is in the presynaptic neuron?

Answer 2

Contains vesicles with neurotransmitters

Question 3

What happens between transmission of neurotransmitter?

Answer 3

• Action potential activates voltage gated calcium channels
• Causes vesicles to travel to membrane and fuse, releasing their neurotransmitter
• Neurotransmitters carry the signal across the synaptic cleft

Question 4

What molecule does ACH colinergic receptor respond to?

Answer 4

Acetylcholine

Question 5

What is Muscarinic?

Answer 5

Minmicks the effects of muscarine (posionous mushroom)

Question 6

What is Nicotinic?

Answer 6

Mimicks the effects of nicotine

Question 7

What stucture does Nicotinic Ach receptor have?

Answer 7

Pentameric structure - ligand gated ion channel

Question 8

What structure does Muscarinic receptors have?

Answer 8

G-protein coupled receptor

Question 9

What are the two transmitters in Autonomic Nervous System (ANS)

Answer 9

Acetylcholine and Noradrenaline

Question 10

What does all the automomic nerve fibres leaving the CNS release? What does it act on?

Answer 10

Acetylcholine. Nicotinic receptors.

Question 11

What does all postganglionic parasympathetic fibres release? What does it act on?

Answer 11

Acetylcholine. Muscarinic receptor

Question 12

What does all the postganglionic sympathetic fibres release? What do they act on?

Answer 12

Noradrealine. Act on α or β adrenoceptors

(excluding sympathetic innervation of sweat glands – Ach-muscarinic receptors )

Question 13

What is the parasympathomimetic?

Answer 13

Mimicks the parasymthetic nervous system

Question 14

What is an agonist?

Answer 14

Molecule binding to the receptor and activate it, causing a response

Question 15

What agonist is Acetylcholine?

Answer 15

An endogenous agonist

Question 16

What are Musarinic antagonists ?

Answer 16

Binds to muscarinic receptors but has no effect

Question 17

What molecules bind to the muscarinic receptors?

Answer 17

Acetylcholine, Carbachol and Bethanechol

Question 18

What is the use of Carbachol and Methacholine?

Answer 18

Diagnosis of asthma (direct action on smooth muscle of airway)

Question 19

What hydrolyses Carbachol, methacholine and bethanechol?

Answer 19

AChE

Question 20

What is the use of Bathanechol on muscarinic receptors?

Answer 20

Alleviate dry mouth and treatment of urinary retention

Question 21

What is Pilocarpine and what does it do?

Answer 21

Partial agonist. Stimulate screction from glands and contracting iris smooth muscle

Question 22

What is the use of Pilocarpine?

Answer 22

Treat dry mouth and eyes after radiation

Question 23

What effect does muscarinic agonists have on the cardia

Answer 23

• Slow heart rate
• Lower force of contraction
• Lower cardiac output

Question 24

What effect does muscarinic agonists have on the vascular system?

Answer 24

• Vasodilation

Question 25

How is Gl tract affected by muscarinic agonist?

Answer 25

Peristaltic activity increases causing colicky pain

Question 26

How is Urinary tract affected by muscarinic agonist?

Answer 26

Relaxes the internal spinchter, promoting emptying of the bladded

Question 27

How is respiratiory tract affected by muscarinic agonist?

Answer 27

- Increased bronchial msucle contration - mucus secretion (No not use if patient has Chronic obstructive pulmonary disorder or asthma)

Question 28

How is Ocular affected by muscarinic agonist?

Answer 28

- PNS nerves to the eys adjust the surature of the lens - mAChRs are activated

Question 29

(CONTINUE FROM PAGE 16)

Question 30

What effect does nicotine has?

Answer 30

- Higher cardiovascular activity - Highter gastrointestinal motility

Question 31

What is Nicotine?

Answer 31

Naturally occurring plant alkaloid

Question 32

What dpoes nicotine cause when activing receptors?

Answer 32

Release dopamine (neurotransmitter)

Question 33

How does drugs block neuromuscular transmission?

Answer 33

1) acting presynaptically to inhibit ACh synthesis or release 2) acting postsynaptically – blocking Ach receptors or persistent depolarisation leading to desensitisation

Question 34

What is Tubocurarine?

Answer 34

Paralysing agent

Question 35

What effect does these clincal drugs have? (pancuronium, pipecuronium vecuromium )

Answer 35

Used during anaethesia and treatment for teatnus and syrchnine posioning

Question 36

What is Curare? Use?

Answer 36

Plant extract alkaloid. Posioned arrows

Question 37

What can reverse Tubocurarine?

Answer 37

AChE inhibitor

Question 38

What reversal drugs are for?

Answer 38

Prevent parasympathomimetic effects

Question 39

How is Deplolarising neuromuscular blocking durgs used?

Answer 39

Bind to Ach and repeated firing of action potentials to tire receptors until it no longer responds

Question 40

What agonist drug is used for depolarising neuromusclar blocking drugs?

Answer 40

Suxametheonium (clincally used)

Question 41

What is Fasciculation?

Answer 41

Muscle twitching before paralysis

Question 42

What is the Pharmacological effects of nicotine?

Answer 42

- Effects the CNS, activiating nicotinic receptor in the brain - Cause neuronal exitation and transmitter release - Desensitisation occur with repeated use (tolerance), increasing receptors and dependence

Question 43

What is the Clinical effects of nicotine?

Answer 43

- Reduces anxiety, enhanced performance (motor and sensory) - Tachycardia, sweating, increased cardiac output and arterial pressure, reduction in GI motility, reduction in food intake

Question 44

What is the Clinical effects of nicotine?

Answer 44

- Reduces anxiety, enhanced performance (motor and sensory) - Tachycardia, sweating, increased cardiac output and arterial pressure, reduction in GI motility, reduction in food intake

Question 45

What effect does first time smokers experience?

Answer 45

Nausea and vomiting

Question 46

How fast is abosption of nicotine is in the lungs?

Answer 46

Rapid

Question 47

WHat are the three type of dependence?

Answer 47

Phsycial, psychological and tolerance

Question 48

What tolerance does to the body?

Answer 48

Desesnsitisation, increase in receptors

Question 49

What effects does withdrawal cause?

Answer 49

Sleep disturbance, irritability, imparied preformance, aggression

Question 50

What does the meslimbic reward pathway cause?

Answer 50

Increase in dopamine

Question 51

Examples of harmful agents

Answer 51

Tar, carbon monoxide, nicotine

Question 52

What is the purpose of Hemicholinium?

Answer 52

Affects acetylcholine systems by blocking transport of choline into the nerve terminal

Question 53

What is the purpose of Vasamicol?

Answer 53

It blocks Ach transport into synaptic vesicles

Question 54

What is α-latrotoxin? What is the purpose of α-latrotoxin ?

Answer 54

Black widow spider vemon.. Stimulat vesicular release of Ach

Question 55

What does α-latrotoxin cause?

Answer 55

Musucle contraction, pain, analgesics, antiflammatories (death is possible)

Question 56

What does Botulinium posioning cause?

Answer 56

Progressive aprasympathetic and motor parlysis

Question 57

What is Botulinium toxin?

Answer 57

Very high potent group of bacterial endotoxins

Question 58

What are Peptidases?

Answer 58

Cleave speicifc proteins involved in exocytosis

Question 59

What does Peptidases do?

Answer 59

Block synapses long term

Question 60

How effected is the Botulinium treatment for toxins?

Answer 60

Given before symptoms appear as actions cannot be reversed if bound

Question 61

What type of antagonists are muscarinic?

Answer 61

Competitive

Question 62

What are the main effects of atropine (muscarinic antagonism)?

Answer 62

- Inhibition of secretion - Tachycardia (increased heart rate) - Dilated pupils become unresponsive to light - Bronchial, biliary and urinary tract smooth muscles are relaxed - Excitaory effects on the CNS

Question 63

What does Scopolamine do to the CNS?

Answer 63

Prevent motion sickness