Neurotransmitters

Question 1

Two Major classes of receptors

Answer 1

Ionotropic Receptors

Metabotropic Receptors

Question 2

In which receptor class is the receptor molecule also an ion channel?

Answer 2

Ionotropic Receptors

Question 3

In which receptor class is the receptor and ion channel are separate molecules?

Answer 3

Metabotropic Receptors

Question 4

Between Ionotropic and Metabotropic Receptors; which is fast and which is slow?

Answer 4

Ionotropic gives rise to a FAST postsynaptic response.

Metabotropic gives rise to a SLOW postsynaptic response

Question 5

Neurotransmitters can be divided into these two groups:

Answer 5

Neuropeptides

Small-molecule neurotransmitters

Question 6

The first substance identified as a neurotransmitters

Answer 6

Acetylcholine (ACh)

Question 7

Are the actions of ACh in the CNS well understood?

Answer 7

No, they are not well understood

Question 8

Acetyl CoA is synthesized from…

Answer 8

glucose

Question 9

ACh is synthesized from

Answer 9

Acetyl CoA and choline.

Question 10

The reaction creating ACh is catalyzed by

Answer 10

Choline Acetyltransferase

Question 11

ACh is terminated by

Answer 11

acetylcholinesterase (AChE)

Question 12

Acetylcholinesterase hydrolyzes ACh into

Answer 12

acetate and choline

Question 13

What happens to choline after it is hydrolyzed?

Answer 13

Choline is transported back into nerve terminals and used to resynthesize ACh.

Question 14

Explain how Organophosphates work on ACh

Answer 14

Organophosphates inhibit ACh at the synapse causing a back up of ACh that depolarizes the postsynaptic cells. The depolarized cell enters a refractory state that does not listen to new incoming ACh coming at it. The result is neuromuscular paralysis and possible death.

Question 15

The most important transmitter in normal brain function

Answer 15

Glutamate

Question 16

Precursor of Glutamate

Answer 16

Glutamine

Question 17

Glutamine is released by these cells

Answer 17

Glial cells

Question 18

Inhibitory neurotransmitters that are most often used in the CNS

Answer 18

Gamma-Aminobutyric Acid (GABA) and glycine

Question 19

GABA is most commonly found in these cells:

Answer 19

local circuit interneurons

Question 20

The predominant precursor for GABA synthesis

Answer 20

Glucose

Question 21

This catalyzes the glutamate to GABA

Answer 21

Glutamic acid decarboxylase (GAD)

Question 22

GAD requires this as a co-factor for synthesis of GABA

Answer 22

pyridoxal phosphate

Question 23

Pyridoxal phosphate is derived from

Answer 23

Vitamin B6

Question 24

A B6 Deficiency can lead to

Answer 24

diminished GABA synthesis

No B6 = no pyridoxal phosphate = no cofactor for GAD =no synthesis of GAD into GABA