ANS L2: ANS Neurotransmitter and receptors

Question 1

For the adrenal gland, once stimulated ACh releases ___ and _____.

Answer 1

NE and E

Question 2

Generally - most blood vessels ______ (vasoconstriction/vasodilation) (excitatory repsonse) but some dilate (ones going to the muscles being highly use- receptors inhibitory response –> relax

Answer 2

vasoconstriction

Question 3

IMPORTANT DIAGRAM

Answer 3

Question 4

Nicotinic and muscarinic receptors are _______ receptors

Answer 4

cholinergic

Question 5

What are receptors for the sympathetic preganglion?

Answer 5

ACH

Question 6

What are receptors for the parasympathetic preganglion?

Answer 6

ACH

Question 7

What are receptors for the sympathetic autonomic ganglion?

Answer 7

Nicotinic

Question 8

What are receptors for the parasympathetic autonomic ganglion?

Answer 8

Nicotinic

Question 9

What are receptors for the sympathetic postganglion?

Answer 9

Adrenaline Noradrenaline

Question 10

What are receptors for the parasympathetic postganglion?

Answer 10

ACH

Question 11

What are receptors for the sympathetic effector cells?

Answer 11

α1, α2, β1, β2 receptors α1, α2, β1, β2 receptors are adrenergic receptors Many subtypes and all have different effects and affinities

Question 12

What are receptors for the parasympathetic effector cells?

Answer 12

Muscarinic

Question 13

IMPORTANT SLIDE

Answer 13

Question 14

Where is the site of the nicotinic receptor?

Answer 14

All autonomic ganglia

• Motor end plate of skeletal muscle fibres
• Some CNS cell bodies and dendrites

Question 15

Where is the site of the muscarinic receptor?

Answer 15

Effector cells (cardiac muscle, smooth muscle, glands)

• Some CNS cell bodies and dendrites

Question 16

What is the response to Ach release from the nicotinic receptor?

Answer 16

• Sympathetic and parasympathetic preganglionic fibres Motor neurons
• Some CNS presynaptic terminals

Question 17

What is the response to Ach release from the muscarinic receptor?

Answer 17

Parasympathetic postganglionic fibres

• Some CNS presynaptic terminals

Question 18

What are the 4 adrenergic receptors?

Answer 18

α1, α2, β1, β2

Question 19

What are the 4 characteristics of α1 receptors?

Answer 19

1. < Adrenaline > Noradrenaline
   
   • (If put equal amounts ore likely to bind more to noradrenaline )
2. Ca 2+ second messenger system
3. Excitatory response, contraction of smooth muscle
4. Arterioles, most sympathetic target tissues

Question 20

What are the 5 characteristics of α2 receptors?

Answer 20

1. < Adrenaline & > Noradrenaline
   
   • Higher affinity for NE
2. Blocks cyclic AMP production
3. Inhibitory response, relaxation of smooth muscle
4. Digestive tract
   
   • If increases NE –> Git starts to slow down its activity

Question 21

What are the 4 characteristics of β1 receptors?

Answer 21

1. ~ Adrenaline & ~ Noradrenaline
2. Cyclic AMP secondmessenger system
3. Excitatory response
4. Heart (kidney, liver)

Question 22

What are the 4 characteristics of β2 receptors?

Answer 22

1. Mostly Adrenaline
   
   • Higher affinity for E
2. Cyclic AMP secondmessenger system
3. Inhibitory response, relaxation of smooth muscle
4. Bronchioles, arterioles

Question 23

You are a drug designer and being asked to develop a drug that reduces heart rate in the treatment of hypertension. Based on todays’ information you would develop a drug that…

EXAM QUESTION

Answer 23

selectively blocks β1 adrenergic receptors thereby reducing the sympathetic effects on the heart. Such drugs (Metoprolol, Atenolol) are called β1 antagonists.

Drug –> beta 1 antagonist (beta blockers)

Selectively blocks beta-1 adreniergic receptors

Additional consequence:

Blocks beta 2

Normal hypotension but have vasoconstriction of brochioles –> might need to take a beta 2 agonist

ACE- angiotensin converting enzyme

RAAS

Angiotensin II –> vasoconstrictor and releases aldosterone –> more water retention –> more blood pressure

ACE inhibitor –> decreases pressure

Calcium channel blocker –> affects the heart directly

Diuretics

Question 24

You are a drug designer and being asked to develop a drug that suppresses salivary and bronchial secretion before surgery. Based on todays’ information you would develop a drug that….

EXAM QUESTION

Answer 24

selectively blocks acetylcholine (ACh) at the muscarinic receptors, thereby blocking the parasympathetic effects. This drug (Atropine) is called a muscarinic antagonist.

Parasympathetic response (muscarinic) –> block muscarinic

Muscarinic antagonists- selectively block Ach at muscarinic receptors

Block NNJ –> paralyse skeletal muscles (keep patients calm and immobile during surgery)

If you wake up to early and skeletal muscles are being paralysed What do you do?

Can be monitored now (in the past it was a problem)

Question 25

You are a drug designer and being asked to develop a drug that dilates bronchioles in the treatment of asthma without undesirably stimulating the heart. Based on todays’ information you would develop a drug that…. **EXAM QUESTION**

Answer 25

selectively activates β2 adrenergic receptors at low doses thereby relaxing the bronchial smooth muscles (the heart has mostly β1 adrenergic receptors). This drug (Salbutamol) is called a **β2 agonist.** Asthma- inflammatory disease of small airways (early dynamic small airway closure) * Beta 2 agonist (activates receptors in small airways --\> bronchiole dilation) * Reliver * Too many puffs of puffer (high dose) * Increase HR (overflows --\> reaches heart --\> activates Beta 1 receptors) * Immediate (when need relieving) * Steroids (anti-inflammatory in small airway --\> dilate) * Not an immediate effect --\> few days

Question 26

You are a drug designer and being asked to develop a drug that increases heart rate and that leads to general vasoconstriction in the treatment of acute cardiac failure. Based on todays’ information you would develop …. **EXAM QUESTION**

Answer 26

**Human adrenaline.** Adrenaline activates α & β adrenergic receptors thereby increasing heart rate, and promoting smooth muscle contraction of peripheral arterioles, which results in increased arterial blood pressure. Adrenaline and noradrenaline activate alpha1 and alpha1 (which need to be activated to increase HR and vasoconstriction) Drug - Adrenaline (used in epi pens) if anaphylaxis --\> vasodilation --\> decrease pressure --\> adrenaline --\> general vasoconstriction

Question 27

You are a drug designer and being asked to develop a drug that reduces the effects of both, sympathetic and parasympathetic NS. Based on todays’ information you would develop a/an: 1. non-specific adrenergic antagonist 2. muscarinic antagonist 3. muscarinic agonist 4. nicotinic agonist 5. nicotinic antagonist **EXAM QUESTION**

Answer 27

5. nicotinic antagonist