GABA Flashcards
What type of ions do GABAa receptors permit the influx of?
Chloride ions
State the type of receptor GABAa is.
Ligand-gated ion channel
Where is GABA synthesised?
Nerve terminals
Which enzyme catalyses the reaction of GABA formation
Glutamate decarboxylase
GABA is re-uptaken by which transporters?
GAT-1 and GAT-2
What receptor type does GABAa activate?
Ligand gated ion channels
What effect does GABA have?
Major inhibitory neurotransmitter
Potential drug targets of GABA.
Give one example
Anxiety disorders.
Benzodiazepines: GABAa +ve allosteric modulators
What is the precursor of GABA
Glucose
The absence of which vitamin has an effect on GABA synthesis?
Why is this dangerous?
Vitamin B6 can lead to diminished GABA synthesis
Dangerous as it can lead to seizures due to the lack of neuroinhibitory drive.
The steps of GABA synthesis
Glutamate
| (Glutamate decarboxylase)
| (Pyridoxal phosphate - Cofactor)
GABA
How is GABA stored?
GABA = stored in oval vesicles
How is GABA degraded?
GABA | (GABA transaminase (GABA-T) Succinic semialdehyde | (Succinic semialdehyde dehydrogenase) Succinic acid
State the two types of neurotransmitter receptors
Ionotropic (Ligand-gated ion channels)
Metabotropic (GPCR)
Give an example of an ionotropic and metabotropic receptor
Ionotropic: GABAa receptor
Metabotropic: GABAb receptor
What effect do inhibitory neurotransmitters have on the membrane potential?
GABA causes HYPERpolarisation
Why does hyperpolarisation occur?
Due to the efflux of K and influx of Cl
Where in the brain are GABA projections?
What are they called?
In the cerebellum
Purkinje cells
Which enzyme is responsible for converting glutamate to GABA
Glutamate decarboxylase
Which GABA re-uptake transporter (GAT) subtype is predominantly expressed on neurons
GAT-1
Which GABA re-uptake transporter subtype is predominately expressed on glial cells
GAT-3
Which subunit interface comprises the GABAa receptor binding (for GABA)
Alpha and beta
Which ions do GABAb receptor permit the efflux of?
K+
GABAa receptor permits the influx of which type of ion?
chloride (Cl-) ions
