Drugs and Addiction

Question 1

Presynaptic neuron alterations

Answer 1

NT Production- inhibit enzymes, transport of raw materials

NT Release- can block APs from ever arriving, or autoreceptors can provide false feedback

NT Clearance- reuptake inhibitors, or block enzymes

Question 2

Postsynaptic neuron alterations

Answer 2

NT Receptors- antagonists block receptors from being activated, agonists mimick NTs

Cellular processes- activate second messengers, genes, protein production

Question 3

Affinity (binding affinity)

Answer 3

How likely the ligand is to bind with a receptor

How long the ligand stays bound (can it actually stay long enough to cause an effect?)

Question 4

Efficacy (intrinsic activity)

Answer 4

How likely the ligand is to have an effect

Antagonist= very low levels of efficacy
Agonist= high efficacy

Question 5

Dose-Response Curve

Answer 5

Relationship between dosage and observed effect (helped to determine useful and unsafe dose ranges)

Therapeutic effect- balance between drug effectiveness and toxicity (want least negative side effects while still getting desired effect)

Question 6

Bioavailability

Answer 6

Free to act on target issue

Not bound or broken down prior to having its effect

Question 7

Biotransformation

Answer 7

Breakdown of drugs into active metabolites, which can have beneficial or harmful effects

Question 8

Blood-brain barrier

Answer 8

Ligand must be able to pass BBB to have an effect

Question 9

Pharmacokinetics

Answer 9

Factors that affect the movement of a drug into, through, and out of the body

Question 10

Tolerance

Answer 10

Building up resistance, and thus only getting a smaller effect with the same dose of a given drug

Metabolic and functional tolerance

Question 11

Metabolic tolerance

Answer 11

Body clears the drug more quickly, so it has less time to take effect

Question 12

Functional tolerance

Answer 12

Receptors respond less to the drug

• down-regulation: decreased # of receptors in response to agonist
• up-regulation: increased # of receptors in response to antagonist

Question 13

Sensitization

Answer 13

Larger effect with the same dose

Particularly common with side effects

Question 14

Cross-tolerance

Answer 14

Tolerance to a particular drug generalizes to other drugs of the same chemical class

Question 15

Dependence and Addiction Models

Answer 15

Moral model- lack of self control or character weakness, it’s all the users fault

Disease model- pathological process, largely uncontrollable

Physical dependence model- withdrawal avoidance

Positive reward model- positively reinforcing effects, dopamine/reward circuit

Question 16

Insula

Answer 16

Region of cortex within lateral sulcus, involved in addiction

Question 17

Dysphoria

Answer 17

Strongly negative feelings that can only be relieved by administration of the withdrawn drug (opposite of euphoria)