Autonomic Physiology 1

Question 1

What does the autonomic nervous system control?

Answer 1

The things you don’t want to think about,
Smooth muscle surrounding blood vessels,
Secretions from glands
Focusing of the eye
GI neurones

Question 2

What are the divisions of the autonomic nervous system?

Answer 2

Sympathetic
Parasympathetic
Enteric

Question 3

Describe the myelination in pre-ganglionic and post-ganglionic fibres in the autonomic nervous system?

Answer 3

Pre-ganglionic (white ramus) fibre is small myelinated, post- ganglionic fibre is unmyelinated

Question 4

Describe the receptors in the NMJ versus the ANS?

Answer 4

NMJ is ionotropic meaning they are ion channels
ANS is metabotropic meaning they are G-protein receptors

Question 5

Where do the nerves in the sympathetic nervous system leave the spine?

Answer 5

Thoracic and the lumbar region.

Question 6

Where do the ganglia lie in the sympathetic nervous system?

Answer 6

Paravertebral ganglia lie in the sympathetic trunk which is close to the spinal cord.
Prevertebral ganglia lie in the collateral ganglia

So trunk = paravertebral, anything else = prevertebral

Question 7

What type of information does the ventral horn carry|?

Answer 7

neurons send fibres to the skeletal muscles, causing muscle contraction

Question 8

What type of information does the dorsal horn carry?

Answer 8

Receive sensory information from all around the body

Question 9

White ramus is what kind of ganglionic fibre and why?

Answer 9

Pre - ganglionic, because of the myelination

Question 10

What are the relevant neurotransmitters and receptors for the sympathetic nervous system and the parasympathetic nervous system?

Answer 10

Sympathetic = noradrenaline and adrenaline - acts on adrenergic receptors alpha and beta
Parasympathetic nervous system = Acetylcholine - acts on cholinergenic receptors - muscarinic and nicotinic receptors

Question 11

What is the grey matter made up of?

Answer 11

Cell bodies of the axons

Question 12

What is white matter made up of?

Answer 12

Axons linking the different parts of grey matter together. Many of these nerve fibers are surrounded by a type of sheath or covering called myelin. Myelin gives the white matter its color

Question 13

Define ganglioin

Answer 13

A structure containing a number of nerve cell bodies, typically linked by synapses, and often forming a swelling on a nerve fibre.

Question 14

How do preganglionic fibres in the sympathetic nervous system work?

Answer 14

Release acetylcholine acting on nicotinic cholinergic receptors

Question 15

How do postganglionic fibres in the sympathetic nervous system work?

Answer 15

Release noradrenaline which acts on alpha and beta receptors

Question 16

Describe the structure of the postganglionic cells of the adrenal medulla

Answer 16

No axon, instead noradrenaline (80%) and adrenaline (20%) is released into the blood.

Question 17

What is the adrenal medulla?

Answer 17

The central portion of the adrenal gland, secretes noradrenaline and adrenaline

Question 18

Where do nerves leave the spine in the parasympathetic nervous system?

Answer 18

Cranial and sacral regions of the spine

Question 19

Where do the ganglia lie in the parasympathetic nervous system?

Answer 19

Close to the target

Question 20

What do preganglionic and postganglionic receptors in the parasympathetic nervous system respond to?

Answer 20

Preganglionic = acetylcholine - nicotinic receptors
Postganglionic = acetylcholine - muscarinic receptors

Question 21

How are sweat glands innervated?

Answer 21

Sympathetic cholinergenic fibers

Question 22

What class of neurotransmitters are NO and peptides?

Answer 22

Nonchollinergenic and nonadregenic receptors