Week 7

Question 1

Glutamate receptor types

Answer 1

• Ionotropic
• Metabotropic

Question 2

Ionotropic Glutamate Receptors

Answer 2

• AMPA (univalent cations: Na)
• NMDA (uni/divalent cations: Na/Ca)

Question 3

What receptor has a plug

Answer 3

NMDA glutamate-R
Mg2+ Extracellular plug
(inh. by PCP)

Question 4

Metabotropic Glutamate Receptors

Answer 4

• 1/5: Gq
• 2/3/4/6/7/8: Gi
  (total 8)

Question 5

Ionotropic receptor structure

Answer 5

• 4 subunits (heterotetramer)
• Each subunit has 3 TM domains
• 10+ types
• Fast / rapid signalling

Question 6

Metabotropic receptor structure

Answer 6

• G-protein coupled
• 8 types

Question 7

What typically causes EPSP

Answer 7

Ligand gated Non-selective cation channel opening

Question 8

What typically causes IPSP

Answer 8

Ligand gated chloride channels (or K+)

Question 9

GABA receptor types

Answer 9

• GABA(A)
• GABA(B)

Question 10

GABA (A) -R

Answer 10

• Ligand gated Cl- channel
• Tranquilizers activate these

Question 11

GABA (B) -R

Answer 11

• G-coupled 7TM receptor
• Gi
• K+ channel opens (BY subunit)

Question 12

GABA (A) -R Structure

Answer 12

• Pentameric (5 subunits)
• Each subunit has 4TM domains
• Analogs: nACh-R, Gly-R, 5-HT3

Question 13

Temporal summation

Answer 13

1 presynaptic neuron releases NT many times over a short period and PSPs are added together

Question 14

Spatial summation

Answer 14

Sum. of PSPs from multiple neurons at the same time which is more powerful than temporal summation

Question 15

Non-adapting pattern

Answer 15

• Quick depol/repol
• VG Na & K+ channels
• High AP frequency

Question 16

Adapting pattern

Answer 16

• Slowly-activating K+ channels (+VG Na/K)
• Increased hyperpol. so AP frequency decreases

Question 17

Rhythmic bursting pattern

Answer 17

• VG Ca+ channels & Ca+ activated K+ channels
• Strong hyperpol. after Ca+ channel opening

Question 18

Burst firing

Answer 18

• Small EPSP cannot reach threshold of VG Na+ channels
• T-type Ca channels open to help reach VG Na channel threshold leading to Burst

Question 19

Types of increased Synaptic Plasticity

Answer 19

• Facilitation: <1s
• Augmentation: seconds
• Potentiation: 10s of s to minutes
• LT-potentiation: hours, days

Question 20

Types of decreased Synaptic Plasticity

Answer 20

• Habituation: inactivity
• Depression: high or persistent low AP freq.
• LT-depression

Question 21

AMPA phosphorylation

Answer 21

Increases synaptic strength

Question 22

Where does LTP happen

Answer 22

Hippocampus

Question 23

What maintains Astrocyte shape

Answer 23

Specific intermediate filament & Glial fibrillar acidic protein (GFAP)

Question 24

Bergmann glial cells

Answer 24

Special astrocytes with parallel processes to purkinje cells

Question 25

2 Types of Astrocytes

Answer 25

- Fibrous (white m) - Protoplasmic (grey m)

Question 26

Neurons energy sources

Answer 26

- Glucose through GLUT3 - Lactate from Astrocytes (GLUT1)

Question 27

What is used to move lactate from astrocyte to neuron

Answer 27

MCT1 & MCT2

Question 28

Astrocyte regulation of K+ levels (Channels)

Answer 28

- Na/K ATPase - Na/K/2Cl cotransport - K channels

Question 29

Neuron resting Em (& increased K+)

Answer 29

-65 mV (+5 mV)

Question 30

Astrocyte resting Em (& increased K+)

Answer 30

-85 mV (+25 mV)

Question 31

Glutamate transporters on Neuron & Astrocytes

Answer 31

- Neuron (EAAT 3) - Astrocyte (EAAT 1/2)

Question 32

Glutamine transporters brain

Answer 32

SNAT

Question 33

Microglial cells

Answer 33

- Macrophages of CNS - 20% of glial - Most effective APC in brain