GABA Signaling Flashcards Preview

Biochemistry Exam III material > GABA Signaling > Flashcards

Flashcards in GABA Signaling Deck (46)
Loading flashcards...
1
Q

GABA stands for

A

Gamma Amino Butryric Acid

2
Q

The amino group of GABA is in the ____ position

A

Gamma

3
Q

The name of GABA is a misnomer because

A

it is not an acid

4
Q

GABA functions as a ______

A

neurotransmitter

5
Q

How is GABA produced

A
  • in metabolic process of cell and then released

- manufactured in cytosol and in vesicles, this allows it to fuse with the membrane and be released

6
Q

What all bind to GABA receptor

A

valium, barbiturates, Gabapentin, Anesthetics, and alcohol

7
Q

GAD (Glutamic acid decarboxylase) catalyzes

A

removes carboxyl group from glutamate to form GABA

and CO2

8
Q

GABA signalling activates neural _____

A

inhibition

9
Q

Reactions of the ______ are responsible for the synthesis, conservation, and metabolism of GABA

A

GABA shunt

10
Q

SSADH (succinic semialdehyde dehydrogenase) catalyzes

A

Succinic semialdehyde + NAD —-> NADH + Succinate

and reverse reaction

11
Q

GABA-T catalyzes

A

Gamm-Amino Butryrate + Alpha-Ketoglutarate ——> Succinic semialdehyde + Glutamate (and reverse reaction)

(also note that B6 (biotin) is required as cofactor)

12
Q

What is the cofactor for GABA-T

A

B6 (Biotin) ( this is the cofactor for all aminotransferases)

13
Q

GABA receptors fall into a class of PLGC receptors what does that stand for

A

Pentameric ligand gated channels

14
Q

How many total membrane -spanning regions does a GABA receptor have

A

20 (5 homologous subunits each of which has four membrane-spanning regions)

15
Q

How many genes code for the GABA receptors subunits

A

19

16
Q

The central core of the GABA receptor is a ____ channel

A

Choride ion channel

17
Q

Benzodiazepine act on GABA receptors by

A

Bind between Alpha1 and Gamma2

extends how long the chloride channels is open
but they still require GABA to open the channel

18
Q

Benzodiazepine binds to GABA receptors at

A

Alpha1 Gamma2 junction

19
Q

GABA has 2 binding sites on a GABA receptor between

A

Alpha1 and Beta2 subunits

20
Q

What terminus of GABA receptors is almost all extracellular

A

N-terminus

21
Q

The C and N terminuses of GABA receptors are

A

extracellular

22
Q

What terminus of GABA receptor binds most of GABA

A

N-terminus

23
Q

What is the major Isoform of GABA receptor

A

alpha1,beta2,Gamma2

24
Q

The alpha1,beta2,Gamma2 isoform of GABA receptors make up about ____% of all GABA receptors in the brain

A

80%

25
Q

Etomidate binding sites for GABA receptor

A

are located in the transmembrane domain at beta/alpha interfaces

26
Q

Phasic inhibition

A

is dependent on the release of neurotransmitter and occurs at the synapse

27
Q

Tonic inhibition

A

is extrasynaptic, as the GABA is taken up at synapse some of it gets out of celft and acts on other neurons (they are acted on by this escaped GABA)

28
Q

Glycine and GABA receptors are bound linked to other Glycine or GABA receptors respectively by what? This creates what factor

A

Gephyrin. This allows for the clustering of the receptors at synapses and dispersion of clusters during plasticity

29
Q

GABA-T catalyzes

A

Gamm-Amino Butryrate + Alpha-Ketoglutarate ——> Succinic semialdehyde + Glutamate (and reverse reaction)

(also note that B6 (biotin) is required as cofactor)

30
Q

What is the cofactor for GABA-T

A

B6 (Biotin) ( this is the cofactor for all aminotransferases)

31
Q

GABA receptors fall into a class of PLGC receptors what does that stand for

A

Pentameric ligand gated channels

32
Q

How many total membrane -spanning regions does a GABA receptor have

A

20 (5 homologous subunits each of which has four membrane-spanning regions)

33
Q

How many genes code for the GABA receptors subunits

A

19

34
Q

The central core of the GABA receptor is a ____ channel

A

Choride ion channel

35
Q

Benzodiazepine act on GABA receptors by

A

Bind between Alpha1 and Gamma2

extends how long the chloride channels is open
but they still require GABA to open the channel

36
Q

Benzodiazepine binds to GABA receptors at

A

Alpha1 Gamma2 junction

37
Q

GABA has 2 binding sites on a GABA receptor between

A

Alpha1 and Beta2 subunits

38
Q

What terminus of GABA receptors is almost all extracellular

A

N-terminus

39
Q

The C and N terminuses of GABA receptors are

A

extracellular

40
Q

What terminus of GABA receptor binds most of GABA

A

N-terminus

41
Q

What is the major Isoform of GABA receptor

A

alpha1,beta2,Gamma2

42
Q

The alpha1,beta2,Gamma2 isoform of GABA receptors make up about ____% of all GABA receptors in the brain

A

80%

43
Q

Etomidate binding sites for GABA receptor

A

are located in the transmembrane domain at beta/alpha interfaces

44
Q

Phasic inhibition

A

is dependent on the release of neurotransmitter and occurs at the synapse

45
Q

Tonic inhibition

A

is extrasynaptic, as the GABA is taken up at synapse some of it gets out of celft and acts on other neurons (they are acted on by this escaped GABA)

46
Q

Glycine and GABA receptors are bound linked to other Glycine or GABA receptors respectively by what? This creates what factor

A

Gephyrin. This allows for the clustering of the receptors at synapses and dispersion of clusters during plasticity