Psychophysiology Lecture #3

Question 1

What are the 2 major aspects of drug influence?

Answer 1

1. Drug Effects: observed changes
2. Sites of action: drug molecule binding sites –> must reach the site before able to affect bx.

Question 2

What does the body do to drugs?

Answer 2

A: absorption
D: distribution
M: metabolism
E: excretion

ADME

Question 3

How many liters of blood is pumped every minute?

Answer 3

5

Question 4

How long does it take the entire volume of blood supply to circulate?

Answer 4

1 minute.

Question 5

Inhalation vs. Insufflation

Answer 5

Inhalation = lungs
Insufflation = nasal passage

Question 6

Intravenous

Answer 6

Fastest and most dangerous.
- 30-60 seconds.

Question 7

What role does the kidney play in metabolizing and excreting drugs?

Answer 7

Primary organ of excretion

Question 8

What role does the liver play in metabolizing and excreting drugs?

Answer 8

Active role in enzymatic deactivation.

Question 9

Dose-Response Curve

Answer 9

Point of maximum effect.

Question 10

Effectiveness of drug is impacted by?

Answer 10

1. Sites of action.
2. Affinity of a drug from its site of action.

Question 11

Affinity

Answer 11

The capacity of a drug molecule to bind to a key site of action.

Question 12

What does the most desirable drug have?

Answer 12

High affinity for sites of action producing therapeutic effects and low affinity for sites of action producing toxic side effects.

Question 13

Effective vs. Toxic Dose

Answer 13

• Effective Dose: 50 (ED50)
• Toxic Dose: 50 (TD50)

Question 14

Therapeutic Index

Answer 14

A quantitive measurement of relative safety of a drug.
- Lower ratio = more dangerous.
- Ideal TI >10

Question 15

Neurotransmitters

Answer 15

A chemical used for neuron-to-neuron communication.
- Stored in presynaptic neuron.
- Released into synaptic cleft.

Question 16

How are neurotransmitters terminated?

Answer 16

• Reuptake
• Enzymatic
• Deactivation/degradation

Question 17

Neuromodulator

Answer 17

A chemical that affects the neurotransmission of a whole group of neurons.

Question 18

Agonist

Answer 18

A molecule that by binding to the receptor stimulates a response = increase in postsynaptic effect.

Question 19

Antagonist

Answer 19

A molecule that by bind go to a receptor blocks or inhibits the response = decrease postsynaptic effect.

Question 20

Amino Acid Neurotransmitters in the brain

Answer 20

1. Excitatory: Glutamate
2. Inhibitory: Gamma-Aminobutyric Acid (GABA)

Question 21

Amino Acid Neurotransmitters in the spinal cord and lower brain stem

Answer 21

1. Excitatory: Glutamate
2. Inhibitory: Glycine

Question 22

Glutamate

Answer 22

“Go”
- Main excitatory neurotransmitter in the brain and spinal cord.

Question 23

What are the 4 main receptors in glutamate?

Answer 23

1. NMDA: long term potential
2. AMPA : effect sodium channels.
3. Kainate: effect sodium channels
4. Metabotropic Glutamate: presynaptic auto receptor.

Question 24

NMDA Receptor

Answer 24

• 6 Binding sites
• When channel is open NMDA receptor allows sodium and calcium into the cell –> depolarization.

Question 25

Requirements for Glutamate to Bind

Answer 25

• Glycine must be attached.
• MG must not be attached–> depolarization.

Question 26

Calcium

Answer 26

Secondary messanger.
- Binds and activates enzymes in the cell.
- Profound biochemical and structural changes occur.

Question 27

GABA

Answer 27

“Stop”
- Stored in presynaptic cleft.
- 5 Binding sites.
- GABA Transporters reuptake; aminotransferase deactivates.

Question 28

Monoamines

Answer 28

Neuromodulators derived from a single amino acid.

Question 29

Dopamine

Answer 29

Movement, attention, learning and the reinforcing effect of substances.

Question 30

Norepinephrine

Answer 30

Vigilance/Alertness.
- Dopamine in vesicles is converted to norepinephrine by a special enzyme.

Question 31

Serotonin

Answer 31

Involved in mood and pain regulation, and the control of eating, sleep, arousal and dreaming.