Key Points

Question 1

Charges on the two layered membrane

Answer 1

Outer has lots of positive ions (like Na and K)
Inner has negatively charged proteins

Question 2

When a signal is received the membrane is….

Answer 2

depolarised.
Both sides become positive

Question 3

Efferent Neurons

Answer 3

Take information from the receptors to the brain
Sensory

Question 4

Signal transmission

Answer 4

• Resting potential
• Stimulus activation
• Depolarization
• Repolarisation
• Hyperpolarisation

Answer 5

Presynaptic membrane or element
Action potential
Activates Ca2+ ion channel
Neurotransmitters
Post synaptic membrane
Exert Action

Question 6

_ receptors seem to increase sympathetic traits and _ receptors tend to decrease them

Answer 6

1 and 2

Question 7

The main _ transmitter in the CNS

Answer 7

Excitatory

Question 8

NMDA receptor

Answer 8

Dual gated Na+/Ca2+ channel
Na+ out, K+ out, Ca2+ in
Voltage and ligand gated, depolarisation required to relieve Mg block
Much slower time course than AMPA

Question 9

AMPAr receptor

Answer 9

Ligand gated Na+ channel
Permeable to Na+ in and K+ out
Ca2+ permeable if there is no GluA2 subunit
Fast excitatory transmission

Question 10

The principle … transmitter in the CNS

Answer 10

Inhibitory

Question 11

GABA A

Answer 11

• Ligand gated ion channels
• Permeable to Cl- ions
• Hyperpolarises membrane
• Primarily postsynaptic
• Mediate fast inhibition

Question 12

GABA B

Answer 12

• G-protein-coupled receptors (GPCR)
• Coupled to Ca2+ and K+ ion channels
• Pre and postsynaptic
• Mediate slow inhibition (seconds-minutes)
• Also inhibit transmitter release

Question 13

Main treatment for anxiety

Answer 13

Benzodiazepines

Question 14

Method of Action of Benzodiazepines

Answer 14

Binds with specific modulatory site on GABA A receptor
Enhances GABA activity
Opening of Cl- channels
Hyperpolarisation of cells
Depression of CNS

Question 15

Nociception

Answer 15

The physical process of detection and transmission of damaging or potentially damaging (noxious) stimuli

Question 16

Sequence of nociception

Answer 16

• Noxious stimulus
• Primary transduction
• Secondary transduction
• Depolarisation and action potential generation
• Transmitter release
• Second order neuron response

Question 17

Opiates

Answer 17

Act on the opioid receptors
Mimic endogenous opioids
Examples: morphine, heroine and fentanyl

Question 18

What is a stroke?

Answer 18

A stroke is a transient or permanent interruption in the cerebral blood supply.
This has a cardiovascular cause and leads to ischaemia, which is a lack of O2 and glucose.

Question 19

Ischaemic stroke

Answer 19

Everything downstream of the blockage becomes ischaemic.
Incidence is 85%
Lower mortality than haemorrhagic

Question 20

Excitotoxicity

Answer 20

• Excessive release of glutamate
• The neurones are “excited to death”
• Ca2+ overload within neurons.

Question 21

Neurodegeneration

Answer 21

Progressive loss (death) of neurons beyond that of the normal aging process.
It is a problem because neurons cannot be replaced.

Question 22

Possible causes of ND

Answer 22

Aggregates - toxicity
Inflammation - microglia going wrong
Oxidative stress - tau
Mitochondrial damage