ANS - Neurotransmitters and receptors

Question 1

ANS

- sympathetic

Answer 1

Sympathetic Preganglion: ACH > Autonomic ganglion:
Nicotinic receptors
> Sympathetic Postganglion: Adrenaline Noradrenaline
> Effector cells:
α1, α2, β1, β2 receptors

Question 2

sympathetic effector cells

Answer 2

Effector cells:
α1, α2, β1, β2 receptors

• are adrenergic receptors

Question 3

ANS

parasympathetic

Answer 3

Parasympathetic Preganglion: ACH > Autonomic ganglion:

Nicotinic receptors > Paraympathetic Postganglion: ACH > Effector cells: Muscarinic receptors

Question 4

cholinergic receptors

Answer 4

Nicotinic and muscarinic receptors are cholinergic receptors

Question 5

Cholinergic Receptors:

Nicotinic receptor

Answer 5

site of receptor:
All autonomic ganglia
Motor end plate of skeletal muscle fibres
Some CNS cell bodies and dendrites

Respond to ACH release from Sympathetic and parasympathetic preganglionic fibres
Motor neurons
Some CNS presynaptic terminals

Question 6

Cholinergic Receptors:

Muscarinic receptors

Answer 6

Site of receptor:
Effector cells (cardiac muscle, smooth muscle, glands)
Some CNS cell bodies and dendrites

Respond to ACH release from
Parasympathetic postganglionic fibres
Some CNS presynaptic terminals

Question 7

Adrenergic receptors

α1

Answer 7

< Adrenaline &amp; > Noradrenaline
- Ca 2+ second- messenger system
- Excitatory response, contraction of smooth muscle
- Arterioles,
most sympathetic target tissues

Question 8

Adrenergic receptors

α2

Answer 8

< Adrenaline & > Noradrenaline

• Blocks cyclic AMP production
• Inhibitory response, relaxation of smooth muscle
• DIT

Question 9

Adrenergic receptors

β1

Answer 9

~ Adrenaline & ~ Noradrenaline
Cyclic AMP second- messenger system
- Excitatory response
- Heart (kidney, liver)

Question 10

Adrenergic receptors

β2

Answer 10

Mostly Adrenaline

• Cyclic AMP second- messenger system
• Inhibitory response, relaxation of smooth muscle
• Bronchioles, arterioles

Question 11

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….

Answer 11

selectively blocks β1, adrenergic receptors therby reducing the sympathetic effects on the heart 
such drugs (metoprolol, atenolol) are called β1 antagonists

Question 12

*** 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….

Answer 12

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

Question 13

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….

Answer 13

selectively activates β2 adrenergic receptors at low doeses thereby relaxing bronchioal smooth muscles (the heart has mostly β1 adrenergic receptors). This drug (salbutamol) is called β2 agonist

Question 14

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 ….

Answer 14

Human adrenaline. Adrenaline activates a and b adrenergic receptors thereby increasing HE, and promoting smooth muscle contraction of peripheral arterioles, which results in increases arterial BP/

Question 15

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

Answer 15

nicotinic antagonist

Question 16

Autonomic agonists and antagonists

Answer 16

drugs are available that selectively enhance or mimic (agonists) or block (antagonists) autonomic responses