GLUTAMATE RECEPTORS

Question 1

this receptor includes ligand binding sites and ion channels (no g-protein are involved)

Answer 1

NMDA receptors

Question 2

the primary ligand binding site of the NMDA receptor is what? what inhibits this?

Answer 2

glutamate or exogenous NMDA (N-methyl-D-aspartate)

AP-5

Question 3

what makes the NMDA receptor unique? (hint 2 other agonist sites)

Answer 3

the requirement for the binding of 2 other agonists simultaneously with glutamate to activate the channel

glutamate site (+glutamate -AP-5)
glycine site (+glycine -kynurenic acid)
polyamine site (+spermidine -diethylenetriamine, enhances)

Question 4

the ion channel of the NMDA is decreased by?

Answer 4

high Mg++, MK-801, ketamine (special K), phencyclidine (PCP or angel dust)

Question 5

this receptor is also called a quisqualate receptor and is widely distributed throughout the CNS. This is a single protein complex containing a Na/Ca pore?

Answer 5

ampa receptor

Question 6

agonist and antagonist of the ampa receptors?

Answer 6

agonist: glutamate, ampa
antagonist: NBQX

Question 7

this receptor is a toxin from algae, and it is an agonist at these receptors? no antagonist for this?

Answer 7

kainate receptor

agonist: glutamate and kainate

Question 8

these were the most recently discovered class of glutamate receptors and have two subtypes, both using g proteins to link effectors?

Answer 8

metabotropic receptors

AP-4
ACPD

Question 9

this metabotropic receptor activates phosphodiesterase in target cells, which catabolizes cAMP and cGMP. AP-4 activation decreases glutamate release suggesting that at least some of these receptors function in presynaptic inhibition of glutamatergic terminals?

Answer 9

AP-4 receptors

Question 10

this metabotropic receptor activation results in phospholipase C stimulation (increase DAG and IP3 leading to CA+) Like AP-4 receptors, ACPD appears to modulate the impact of other synapses?

Answer 10

ACPD receptors

Question 11

the Ca++conductance of NMDA channels has been implicated in stimulating _____? what else has it been implicated in?

Answer 11

plasticity

post ischemic cell damage/death, this model called excitotoxicity, the NMDA antagonist MK-801 decreasing excitotoxicity

Question 12

these diseases also involve NMDA and AMPA receptor activation?

Answer 12

ALS (lou Gehrigs disease) and Huntington’s disease