ANS

Question 1

Neurotransmission in ANS

-within autonomic ganglia
main NT
receptor

Answer 1

Acetylcholine is the main neurotransmitter

Binds to nicotinic receptors on postganglionic neurons:

Ionotropic ligand-gated (fast):

Acetylcholine opens pore

• Depolarises neuron

Question 2

Neurotransmission in ANS

-within adrenal medulla
main NT
receptor

Answer 2

Acetylcholine is also the main neurotransmitter

Binds to nicotinic receptors on chromaffin cells

Causes release of adrenalin/noradrenalin into circulation

• Direct activation of sympathetic effector organs

Question 3

Neurotransmission in ANS

-postganglionic sympathetic neurons
main NT
receptor

Answer 3

Noradrenaline is the main neurotransmitter

Binds to adrenergic receptors on the effector organ:

– Metabotropic G-protein coupled (slow)

Question 4

Neurotransmission in ANS

-postganglionic parasympathetic neurons
main NT
receptor

Answer 4

ACh

muscarinic receptor

GPCR

Question 5

Auerbach’s

Answer 5

Regulates muscle contraction

Question 6

Meissner’s

Answer 6

Regulates glandular secretions

Question 7

Horner’s syndrome

-3 classical features

Answer 7

disruption of sympathetic supply to the head

1. constricted pupil (miosis)
2. drooping of eyelid (ptosis),
3. lack of sweating on face (anhidrosis)

Question 8

Which cranial nerves are the only nerves to have parasympathetic component?

Answer 8

3, 7, 9, 10

CN3- Edinger Westphal nucleus
CN7- Superior salivatory nucleus
CN8- Inferior salivatory nucleus
CN10- Nucleus ambigious, dorsal motor nucleus