Autonomic Nervous System

Question 1

Neuroeffector sites/cells innervated by ANS

Answer 1

Smooth muscle
Cardiac muscle
Exocrine glands

Question 2

2 important neurotransmitters in the ANS

Answer 2

Acetylcholine
Noradrenaline

Question 3

ANS neurotransmitters

Answer 3

Nicotinic
Muscarinic
Adrenergic=sympathetic
Cholinergic= parasympathetic

Question 4

Homeostasis

Answer 4

The tendency towards a relatively stable equilibrium between interdependent elements

Question 5

Sympathetic ANS

Answer 5

Tends to activate organ

Question 6

Parasympathetic ANS

Answer 6

Tends to inactivate organ

Question 7

Both systems help maintain homeostasis in:

Answer 7

Adjustment to stress
Preparation for combat
Defecation
Urination
Digestion
Salivation
Adjustment to temperature changes
Protection of eyes against bright light
Respiration
Accommodation of near vision
Maintenance of blood pressure at optimal level

Question 8

Parasympathetic: rest and digest

Answer 8

Decrease HR, B.P, Eyes adjust for light
Emptying of bowel, bladder
Airways constrict

Question 9

Sympathetic: fight or flight

Answer 9

Increase HR, B.P, eyes adjust for dark
Digestion slowed
Airways opened

Question 10

Neurotransmitter

Answer 10

A chemical substance which is released at the end of a nerve fibre by the arrival of a nerve impulse and, by diffusing across the synapse or junction, effects the transfer of the impulse to another nerve fibre, a muscle fibre or some structure

Question 11

PARASYMPATHETIC NERVOUS SYSTEM

Answer 11

Has one neurotransmitter
>acetylcholine
Ach is responsible for the transmission of nerve impulses to effector cells od pns
Ach is easily destroyed by enzyme acetylcholinesterase(AchE)

Question 12

Important neurotransmitters of the ANS

Answer 12

Acetylcholine and noradrenaline

Question 13

The synapses of the neurotransmitters

Answer 13

Cholinergic
Adrenergic synapses

Question 14

Acetylcholine receptors

Answer 14

Nicotinic receptors
Muscarinic receptors

Question 15

Acetylcholine sites

Answer 15

All autonomic ganglia
Parasympathetic postganglionic terminals

Question 16

Antagonists

Answer 16

Antagonists possess affinity but lack efficacy
They block receptor activation by agonists

Question 17

Antagonists and agonists

Answer 17

Agonists: nicotine and muscarine
Antagonists: curare and atropine
IN THAT ORDER
Receptors: nicotinic receptor and muscarinic receptor

Question 18

Curare

Answer 18

It is a poison and it can paralyse a person

Question 19

Indirect acting cholinomimetics
Drug and biological toxins

Answer 19

Excessive release of Ach- latrodectism
Blocks release of Ach- botulism
Inhibit acetylcholinesterase enzyme

Question 20

Latrotoxin( a toxin from the black widow spider)

Answer 20

Produces an explosive release of Ach, causing muscular spasm

Question 21

Botulinum toxin

Answer 21

Prevents Ach release
It is very rarely responsible for serious food poisoning
No antivenom in SA
Causes paralysis
Get rid of wrinkles

Question 22

Botulinum toxin indications

Answer 22

Hyperhidrosis of the axillae and palms- not permanent(sweat)
Type A toxin is used in the treatment blepharospasm (spasmodic eye closure) and hemi-facial spasms

Question 23

Enzymatic degradation of Ach

Answer 23

1. Synthesis of Ach
2. Uptake into storage vesicles
3. Release of neurotransmitters
4. Binding to the receptor
   5.Degradation of Ach
   > Ach is rapidly hydrolysed by AchE
   6.Recycling of choline

Question 24

Drugs used to increase Ach conc.

Answer 24

Physostigmine
Neostigmine

Question 25

Insecticides that inhibit AchE

Answer 25

Carbamates
Organophosphates
> they can cause poisoning

Question 26

Muscarinic features (DUMBELS)

Answer 26

Diarrhoea
Urination
Miosis
Bronchospasm
Emesis
Lachrymation
Salivation

Question 27

Muscarinic blockers

Answer 27

Ipratropium
Scopolamine
Atropine> the most known

Question 28

Side effects of blockade of Ach at Muscarinic receptors

Answer 28

Dry mouth
Constipation
Tachycardia
Decreased sweating
Blurred vision
Confusion
Decreased urination