Module 7 Dose Response Relationships

Question 1

Pharmacodynamics

Answer 1

• Study of what drug does to body
• Biological & chemical effects
• Mechanisms to produce effects

Question 2

Dose Response Curves

Answer 2

• Increasing dose increases response
• Monotonic
• Semi-logarithmic, not linear

Question 3

Dose Response Curve Phases

Answer 3

• 1, dose too low to cause response
• 2, graded response & nearly linear
• 3, larger dose, toxicity risk

Question 4

Efficacy

Answer 4

• Measure of effectiveness of drug at certain dose

Question 5

Maximal Efficacy

Answer 5

• Maximum effect drug can achieve
• Maximum height of dose curve

Question 6

Potency

Answer 6

• Amount of drug to elicit response
• Compare drugs of same effect

Question 7

Higher Potency

Answer 7

• Smaller dose to achieve effect

Question 8

Determining Potency

Answer 8

• Compare dose required to produce half max response
• ED50
• Lower ED50 = high potency

Question 9

Drug Receptors

Answer 9

• Cellular macromolecules
• Binding of molecule to target
• Complex produce biological effect

Question 10

Antacid Actions

Answer 10

• Neutralize stomach acid
• Provide relief of GI disorders
• No target cell for binding

Question 11

Receptor Types

Answer 11

• Ligand gated ion channels
• G-protein coupled receptors
• Enzyme linked receptors
• Intracellular receptors

Question 12

Gated Ion Channels

Answer 12

• Ion movement causes instantaneous changes in function
• Ions require special channels

Question 13

Ligands

Answer 13

• Drug/endogenous molecules
• Control open/close of channels

Question 14

GABA Receptor

Answer 14

• Type of ligand gated channel
• Neurotransmitter
• Opens channel
• Allows chloride into cell

Question 15

Benzodiazepine Drug Class

Answer 15

• Bind to GABA receptor
• Allow chloride into cell

Question 16

GABA Activation

Answer 16

• Sedation
• Muscle relaxation
• Increase intracellular chloride

Question 17

G-Protein Coupled Receptors (GPCRs)

Answer 17

• Seven transmembrane spanning protein receptor
• G-protein with 3 subunits
• Effector molecule (enzyme)

Question 18

GPCR Actions

Answer 18

• Binding of ligand to GPCR activates G-protein
• G-protein dissociates from receptor
• Effector is activated
• Short time response

Question 19

GPCR Neurotransmitters

Answer 19

• Norepinephrine
• Serotonin
• Histamine

Question 20

Enzyme Linked Receptors

Answer 20

• Span cell membrane
• Ligand binding outside membrane
• Enzyme catalytic site inside membrane

Question 21

Enzyme Linked Receptor Response

Answer 21

• Binding to ligand outside activates enzyme inside
• Very rapid

Question 22

Insulin Receptors

Answer 22

• Enzyme linked receptor
• Causes phosphorylation & effector activation
• Increases translocation of glucose transporters too membrane
• Increased glucose uptake & utilization

Question 23

Intracellular Receptors

Answer 23

• Inside cell
• Transcription factors
• Highly lipid soluble

Question 24

Access to Intracellular Receptors

Answer 24

• Ligands must cross membrane
• Diffusion/drug transport protein

Question 25

Intracellular Receptor Binding

Answer 25

• Binding of ligand causes translocation of complex to nucleus
• Binding to DNA
• Stimulates messenger RNA

Question 26

Intracellular Receptor Response

Answer 26

• Delayed protein synthesis

Question 27

Intracellular Receptor Ligand Examples

Answer 27

• Steroid hormones
• Testosterone
• Estrogen

Question 28

Receptor Selectivity

Answer 28

• Bind to one receptor
• Less likely to produce side effects
• Side effects may occur if multiple receptors