Lecture 2

Question 1

What are the difference between the sympathetic and parasympathetic nervous system?

Answer 1

Location in the spinal cord where the nerves arise from

Question 2

Name the two neurones

Answer 2

Post ganglionic neurone and preganglionic neurones

Question 3

Define preganglionic neuron

Answer 3

Cell body in the CNS, small diameter and myelinated, synapses at the autonomic ganglia

Question 4

Define post ganglionic neuron

Answer 4

Cell body in the ANS
Small diameter, unmyelinated
Synapse close to target organ

Question 5

What is the autonomic ganglion?

Answer 5

The interface between the pre and post ganglionic neurones of the ANS in both sympathetic and parasympathetic branches

Question 6

What are nicotinic receptors?

Answer 6

Ion channel receptors the channel opens and allows the movement of sodium into the cell and movement of potassium out of the cell

Question 7

Name the 3 classes the nicotinic receptors fall in to

Answer 7

Neuromuscular junction, CNS, and autonomic ganglion

Question 8

Describe the nicotinic receptors in autonomic ganglia

Answer 8

Ligand gated ion channels, contain alpha3 subunit, cation channel, sodium in and potassium out which generates the threshold potential which triggers the action potential which then triggers the release of Ach, fast EPSP
When threshold potential is reached an action potential is generated in post ganglionic cell

Question 9

What is the main effect of the sympathetic nervous system in the airway?

Answer 9

Flight or flight response

Question 10

What is the main affect of the parasympathetic nervous system in the airway?

Answer 10

Cause construction of the airway

Question 11

Describe sensory nerve pathways in the airway

Answer 11

Trigger the epithelial cells which activates the sensory nerves and they signal to the CNS. The CNS sends a signal back to your airways and something will happen e.g. if the signal was from the sympathetic nervous system then it would cause relaxation

Question 12

What do the posysynaptic fibres release?

Answer 12

Release Ach which acts on muscarinic receptors

Question 13

Describe the selectivity of adrenoceptors

Answer 13

Relatively unselective for 2 endogenous adrenergic neurotransmitters

Question 14

Where is NA more potent

Answer 14

At alpha and beta 1 adrenoreceptors

Question 15

Where is A more potent

Answer 15

At alpha 2 and beta 2 adrenoreceptors

Question 16

Function of alpha1 adrenoreceptors

Answer 16

Construct smooth muscle except in the Gi tract where it relaxes

Question 17

Function of alpha 2 adrenoceptors

Answer 17

Presynaptic inhibition of neurotransmitter release

Question 18

Function of beta 1 adrenoreceptors

Answer 18

Increased heart rate and force of contriction

Question 19

Function of beta 2 adrenoreceptors

Answer 19

Dilates/releases smooth muscle

Question 20

Function of beta 3 adrenoreceptors

Answer 20

Thermogenesis in skeletal muscle