Neurotransmitters, Other Transmitters, And 2Nd Messengers

Front 1

Molecule that can bind a receptor

Back 1

Ligand

Front 2

Ligand that binds to and acivates a receptor

Back 2

Agonist

Front 3

Lignad that binds to and prevents activation of a receptor

Back 3

Antagonist (may or may not be competitive)

Front 4

What are the three families of ligand-gated receptors?

Back 4

1) ATP 2) ACh, GABA & Glycine 3) Glutamate

Front 5

What are the two classes of neurotransmitter action?

Back 5

1) Ligand Gated pore 2) 2nd Messenger System

Front 6

What are the three families of Glutamate Receptors?

Back 6

1) NMDA 2) Kainate 3) AMPA
These are three classical ionotropic glutamate receptors

Front 7

Neither Kainate or AMPA receptors allow ____ to flow whereas NMDA receptor does under certain circumstances/

Back 7

Ca2+

Front 8

CNQX drugs block which receptors?

Back 8

Only Kainate and AMPA- not NMDA

Front 9

AAPV drugs block which receptors?

Back 9

NMDA - not Kainate or AMPA receptors

Front 10

PCD and MK801 block which receptors to produce the effects that resemble hallucination assoc. with schizophrenia?

Back 10

Block NMDA receptors

Front 11

Antipsychotic drugs enhance the current flow through the _____ receptor channels.

Back 11

NMDA receptor channels.

Front 12

___ ____ plug the NMDA receptor ionophore at membrane potentals close to rest.

Back 12

Mg2+

Front 13

What causes the Mg2+ ion plug to be ejected from the NMDA receptor?

Back 13

The depolarization of the cell though the entry of Na+ through the AMPA receptor induced by the binding of Glutamate.

Front 14

The gutamate receptors can also be activated by what?

Back 14

Aspartate (thought to act as a transmitter by some neurons).

Front 15

Excitatory amino acids are ________ while inhibotory amino acids are _________.

Back 15

Dicarboxylic and Monocarboxylic.

Front 16

What are the two inter-related pools of gultamate?

Back 16

Metabolic and Transmitter

Front 17

Which pool of glutamate is present in all cells?

Back 17

Metabolic

Front 18

Which pool of glutamate is located in the vesicles of presynaptic neurons?

Back 18

Transmitter

Front 19

The presence of what near the synaptic junction is critical to help maintain the proper balance in the glutamate system?

Back 19

Glia

Front 20

Which receptors are involved in Long Term Potentiation?

Back 20

NMDA

Front 21

Long term potentiation can be prevented by what?

Back 21

NMDA agonists: APV or MK-
801

Front 22

______ _______ produces a lasting change that enables the terminal to release a greater amount of glutamate when subsequently activated.

Back 22

Retrograde Signal (results from increased Ca2+ in the cytosol)

Front 23

______ removes the Mg2+ block from ________ which, with glutamate, allows Ca2+ to enter the post-synaptic cell.

Back 23

Depolarization, NMDA receptor channel

Front 24

_____ functions as the key excitatory transmitter in the CNS.

Back 24

Glutamate

Front 25

NName the two ionotropic receptors that are present throughout the CNS and have channels selective for Cl- ions.

Back 25

Glycine and GABA (both have a reversal potential of -70)

Front 26

Most common inhibitory transmitter in the CNS

Back 26

GABA

Front 27

How is Glutamate Acid Decarboxylase (GAD) used?

Back 27

As a marker for GABA neurons because GABA is synthesized by this enzyme.

Front 28

______ have Cl- ionopore and is responsible for the classical post-synaptic IPSP

Back 28

GABA A receptor

Front 29

_______ are located pre-synaptically, are metabotropic and impt for presynaptic inhibition.

Back 29

GABA B receptors

Front 30

____ is taken up by neurons and Glia and recycled via Krebs Cycle and Glutamate.

Back 30

GABA

Front 31

_______ and ________ both acti via the GABA system by enhancing the binding of GABA to its receptors and potentiating its actions.

Back 31

Benzodiazepines and Barbituates

Front 32

A drug that acts as a very effcient GABA agonist.

Back 32

Baclofen

Front 33

What two things synthesize ACh?

Back 33

Acetyl CoA and enzyme ChAT.

Front 34

_______ is used as a marker for cholinergic receptors in the CNS

Back 34

ChAT

Front 35

Which toxin acts by binding presynaptically to high-affinity recognition sites on the cholinergic nerve terminals? What effect does this have?

Back 35

Botulinum toxin. This decreases the release of ACh and causes a neuromuscular blocking effect.

Front 36

Which three toxins bind and inhibit nicotine ACh receptor activity?

Back 36

Bungarotoxin, Curare, and Hexamethonium.

Front 37

Which toxin blocks re-uptake of choline by high affinity transporter ChT?

Back 37

Hemicholinium.

Front 38

Which toxin is a reversible inhibitor of Ach esterase?

Back 38

Physostigmine (eserine)

Front 39

Which toxin is a competetive antagonist for muscarinic ACh receptors (mAChRs)?

Back 39

Atropine

Front 40

What is the most abundant family of receptors in the CNS?

Back 40

Glutamate

Front 41

What are the primary inhibitory receptors in the CNS?

Back 41

Glycine and GABA

Front 42

______ _______ leads to an increase in the amount of glutamate stored in the presynaptic vessicles.

Back 42

Retrograde Signal

Front 43

Glutamate Toxixity or Excitotoxicity occurs as a result of what?

Back 43

Occurs when glutamate (specifically NMDA) receptors are activated excessively and the Ca2+ that enters the cell exceeds its ability to sequester or remove it from the extracellular space.

Front 44

The receptors for GABA and Glycine are both ionotropic and selective for which ion?

Back 44

Cl-

Front 45

GABA-A and Glycine receptors are most commonly found where?

Back 45

Postsynaptically

Front 46

Which inhibitory neurotransmitter is taken up by glial cells in the region of the synapse and becomes part of the krebs cycle for that cell?

Back 46

GABA

Front 47

Where are many of the small molecule transmitters synthesized and/or recycled?

Back 47

At the nerve terminal

Front 48

Which neurotransmitters must be synthesized at the cell body?

Back 48

Peptide neurotransmitters

Front 49

Peptides that affect neuronal activity and are thought to have modulatory roles in the CNS.

Back 49

Neuroactive peptides

Front 50

3 types of catecholamines

Back 50

Dopamine, Norepinephrine, and Epinephrine

Front 51

Type of small molecule transmitters known as indolamines

Back 51

Serotonin

Front 52

What is the rate limiting enzyme of the pathway creating catecholamine neurotransmitters?

Back 52

Tyrosine Hydroxylase.

Front 53

What is the immediate precursor to dopamine? How can it be used?

Back 53

L-Dopa, it allows by-passing of the rate limiting step in the creation of the catecholamines.

Front 54

When dopamine is released from the nerve terminal as a transmitter, how is it removed from the synaptic cleft?

Back 54

It is either taken up by the nerve terminal and recycled or broken down by MAO.

Front 55

Where is the largest concentration of dopaminergic neurons?

Back 55

In the substantia nigra (located in the midbrain)

Front 56

Where is the largest concentration of noradrenergic (norepinephrinergic) neurons?

Back 56

In the pontine nucleus Locus Coeruleus.

Front 57

What is the Locus Ceruleus thought to be involved in?

Back 57

Attention, arousal and sleep.

Front 58

Where is the largest concentration of of serotonergic neurons?

Back 58

In the Nucleus Raphe in the medulla.

Front 59

Serotonin that remains in the extracellular space is degraded by what?

Back 59

MAO

Front 60

Which two neuropeptides are involved in the response to painful stimuli?

Back 60

Enkephalins and Substance P

Front 61

Which neurotransmitter participates in both the peripheral response to pain and the central response to pain?

Back 61

Substance P

Front 62

Which neurotransmitter it co-packaged and co-released with almost all other neurotransmitters?

Back 62

ATP

Front 63

Describe the co-transmission of ATP and adenosine.

Back 63

At some synapses in the CNS they are packaged together in the same synaptic vesicle and released together in the neuronal terminals.

Front 64

________ is a modulator of the ACh receptor, acting to increase the force of a resulting muscle contraction by mobilizing the 2nd messenger adenylyl cyclase.

Back 64

CGRP (calitonin gene-related peptide)

Front 65

Term used to describe 2nd messenger mediated events that accounts for the long-lasting effects of some neurotransmission.

Back 65

Cascades

Front 66

Describe the two modes of action of 2nd messenger systems.

Back 66

1. They alter the membrane potential by altering the activity of gated channels
2. They induce metabolic pathways in the cell leading to long-term changes in protein synthesis and function

Front 67

Group of transmembrane proteins that can move about the cell membrane making contact with other transmembrane and cytosolic proteins. Common to all second messenger systems

Back 67

G-Proteins

Front 68

Processes dependent on G proteins coming into contact with other mobile proteins.

Back 68

Collision Coupled Mechanisms

Front 69

Enzyme that gives rise to the second messenger cAMP

Back 69

Adenylyl Cyclase

Front 70

Enzyme that gives to the second messengers inositol polyphosphate (IP3) and Diacyl Glycerol (DAG)

Back 70

Phospholipase C

Front 71

Enzyme that gives rise to the second messenger arachidonic acid

Back 71

phosphlipase A2

Front 72

What are the effects of the adnylyl cyclase system giving rise to the release of cAMP?

Back 72

Activation of cAMP dependent protein kinases that have short and long term effects on channel function and up-regulate protein synthesis.

Front 73

What is the end result of the phospholipase release of IP3-DAG?

Back 73

The mobilization of intracellular calcium from the SER which can lead to opening of Ca2+ dependent K+ channels (short-run) and increased protein synthesis (long-run)

Front 74

What are the effects of the production of arachidonic acid?

Back 74

The production of prostaglandins, leukotrienes and other molecules involved in inflammation.