Pharmacology Block D- Lecture 1

Front 1

What does GABA mean

Back 1

Gamma amino butyric acid

Front 2

What is GAD

Back 2

Glutamate decarboxylase

Used to convert glutamate to GABA

Front 3

Where is GABA exclusively going

Back 3

Brain tissue

Front 4

Where is GABA found within the brain

Back 4

Striatum

Substantia niagra

Hippocampus

Golbus pallidus

Front 5

Where is GABA formed

Back 5

Nerve terminals from glutamate

Front 6

What can the synthesis of gaba be catalysed with

Back 6

Glutamic acid decarboxylase

Front 7

What does the gaba transporter do

Back 7

Terminates synaptic action

Front 8

What are the four variants of GAT

Back 8

GAT1

GAT2

GAT3

BGT1

Front 9

What are the two properties of binding gaba to the brain

Back 9

Saturable

Specific

Front 10

What are the two main classes of gaba binding sites

Back 10

Gaba receptor

Gaba uptake site

Front 11

Is the gaba receptor sodium dependent

Back 11

No

Front 12

What are the three properties of gaba uptake sites

Back 12

Greatly outnumber gaba receptor sites

Neuronal and non neuronal

Binding is sodium dependent

Front 13

What is the potency rank to displace 3[H]-GABA

Back 13

Isoguvaine> muscimol> GABA> gaboxadol(THIP)

Front 14

Does bicuculline displace gaba

Back 14

No

Front 15

Does picrotoxin displace gaba

Back 15

No

Front 16

Where does picrotoxin bind

Back 16

Different binding site to gaba

Bind to chloride ion channel

Front 17

What also acts on picrotoxin binding site

Back 17

Barbiturates

Front 18

What are the two subclass of gaba receptor

Back 18

GABAa

GABAb

Front 19

What are the two subtypes of gaba receptor

Back 19

Baclofen

bicuculline

Front 20

What are the properties of GABAa

Back 20

Bicuculline sensitive

Baclofen insensitive

Front 21

What are the properties of GABAb

Back 21

Bicuculline insensitive

Baclofen sensitive

Front 22

What type of gaba receptors are ionotropic

Back 22

GABAa

It’s a chloride ion channel

Front 23

What type of GABA receptors is metabotrophic

Back 23

GABAb

It is a GPCR

Front 24

What is the structure of GABAa receptor complex

Back 24

Ligand gated chloride ion channel

Has 5 subunits

A 4TM structure

Front 25

What is the most common mix of receptor complex

Back 25

2x alpha

2x beta

1x gamma

Front 26

What does rho not contribute to

Back 26

Classical GABAa receptors

Front 27

What are the binding sites of GABAa

Back 27

Two intervals between alpha and beta

Interface between alpha and gamma

Front 28

What other receptor has a similar structure to GABAa

Back 28

GABAa-rho

Front 29

What is GABAa-rho composed of

Back 29

Five subunit ligand gated ion channel

Three rho subunit varieties

Front 30

Where is GABAa-rho found

Back 30

Retinal bipolar cells

Front 31

What is the pharmacology behind GABAa-rho

Back 31

Insensitive to bicuculline, barbiturates, benzodiazepines, Baclofen

Sensitive to CACA,TPMLA, picrotoxin

Front 32

What is the structure of GABAb receptor complex

Back 32

Metabotropic receptor

Heterodimer of tel 7TM receptors

Couples to Gi/Go

Front 33

What does it mean that GABA is a inhibitory synaptic neurotransmitter

Back 33

It suppresses neuronal activation

Front 34

What does it mean that GABA is involved in presynaptic inhibition

Back 34

Axo axonal inhibition

Front 35

What does it mean that GABA is involved in postsynaptic inhibition

Back 35

Recurrent inhibition

Front 36

Where does presynaptic inhibition occur

Back 36

Spinal cord

Front 37

What does presynaptic inhibition do

Back 37

Reduced transmitter release from terminals of primary accident fibre

Front 38

What connections does presynaptic inhibition require

Back 38

Axo Axonal synaptic connections

Front 39

Where does gaba most effect

Back 39

Brain

Front 40

What does postsynaptic inhibition do

Back 40

It creates increased chloride flux postsynaptically

Front 41

What does a chloride influx do to the membrane

Back 41

Stabilises it

Front 42

What is recurrent inhibition in terms of stimulating incoming pathways

Back 42

Excitation followed by inhibition of outgoing pathway

Front 43

What is axon colateral and we’re is it from

Back 43

From axon of pyramidal cell

Activates GABA interneuron

Interneuron inhibits firing of pyramidal cell

Front 44

What is preventing bursting discharge is terms of recurrent inhibition

Back 44

Reduced max firing rate of pyrimidal cells

This is a feature of epilepsy (bursting discharge)

Front 45

How does muscimol effect recurrent inhibition

Back 45

Enhances it

Front 46

What effect does bicuculline have on recurrent inhibition

Back 46

Reduces it