Deck 7: Glutamate and GABA

Question 1

Excitatory amino acid transporters (EAATs)

A) may be defective in the disorder ALS or Lou Gehrig's disease.
B) are found on vesicle membranes in astrocytes and neurons.
C) are found almost exclusively on neurons in the CNS.
D) come in two different varieties, EAAT1 and EAAT2.

Answer 1

may be defective in the disorder ALS or Lou Gehrig's disease.

Question 2

The presence of vesicular glutamate transporters and vesicular monoamine transporters in the same neurons suggests that

A) cells that contain a lot of glutamate must store it in multiple types of vesicles.
B) glutamate can be co-released as a neurotransmitter along with dopamine or serotonin.
C) vesicular transporters are not selective.
D) gene expression has gone wrong in these neurons.

Answer 2

glutamate can be co-released as a neurotransmitter along with dopamine or serotonin.

Question 3

Why is it difficult to assign specific functional roles to glutamate, relative to other neurotransmitters?

A) Because it is found throughout the brain
B) Because it has very limited activity except in particular neural pathways
C) Because its inhibitory action on the cortex makes it difficult to interpret
D) Because it is not found in cortical neurons

Answer 3

Because it is found throughout the brain

Question 4

Which statement about ampakines is false?

A) They may reduce the rate of AMPA receptor desensitization.
B) They enhance the action of glutamate at AMPA receptors.
C) They replace glutamate at its binding site on the AMPA receptor.
D) They improve performance in the DMS task.

Question 5

What evidence does not support the role of NMDA receptors in learning and memory?

A) NMDA receptor antagonists disrupt the acquisition of spatial learning tasks.
B) There are many NMDA receptors found in the hippocampus.
C) CX717 enhances cognitive function.
D) Doogie mice that overexpress the NR2B subunit show enhanced LTP.

Question 6

Chronic treatment with ampakine (CX929) to "middle-age" rats

A) increased their body weight by 25% relative to same aged controls.
B) enhanced dendritic growth of their hippocampal CA1 neurons relative to same-aged controls.
C) reduced the number of dendritic spines of hippocampal CA1 neurons relative to same-aged controls.
D) had no effect on dendrites relative to controls.

Question 7

The excitotoxicity hypothesis states that

A) repeated stimulation of neurons is the basis for learning and memory.
B) tetanic stimulation of the presynaptic neuron can produce LTP in the recipient cell.
C) overexposure to excitatory amino acid transmitters can result in depolarization and cell death.
D) glutamate and aspartate play a critical role in the action of drugs like PCP.

Question 8

Which statement about ischemia is false?

A) It involves a massive decrease in glutamate release.
B) It can result from a stroke or a heart attack.
C) It involves disruption of blood flow and oxygen to tissue.
D) It may be treated with glycine antagonists.

Question 9

The best current treatment for amyotrophic lateral sclerosis (ALS) works on which neurotransmitter system (and thus suggests its' involvement)?

A) GABA
B) Glutamate
C) Dopamine
D) Norepinephrine

Question 10

Which statement about GABA is false?

A) It is found in many local interneurons.
B) It is found in projection neurons carrying inhibitory information.
C) It is found in Purkinje cells of the cerebellar cortex.
D) It is found only in subcortical locations.

Question 11

The fly agaric mushroom produces all of the following effects except

A) macroscopia.
B) hypothermia.
C) anorexia.
D) hallucinations.

Question 12

The classic GABA_A agonist _______ and the noncompetitive GABA_A antagonist _______ both come from plants.

A) muscimol; picrotoxin
B) muscimol; pentylenetetrazol
C) baclofen; picrotoxin
D) bicuculline; baclofen

Question 13

GABA_B receptors are unusual because

A) they require glycine as a co-agonist.
B) they are metabotropic but are composed of subunits.
C) they simultaneously enhance Na⁺ channel opening and inhibit cAMP.
D) they act as autoreceptors.

Question 14

Briefly describe how data from a mouse model of amyotrophic lateral sclerosis (ALS) supports the role of the glutamate system.