Flashcards: Quantifying Pharmacodynamics

amount of a drug administered to an organism

amount of drug in a given compartment

the maximal effect produced by the drug

Not all drugs reach 100% effect in the system, but they still reach their Emax. T/f?

the concentration of a drug that produces 50% of its maximal effect

the concentration/dose required to produce an effect of a given intensity

measure of the strength and probability that a drug will bind an available receptor at a given time

the equilibrium dissociation constant when half of the drug is bound and the other half is unbound.

the maximal amount of receptors bound by drug at plateau

Which is usually greater? EC50 or Kd

What does low kd signify ?

Why aren't EC₅₀ and K_d always the same?

the total # of receptors present vs total # of receptors needed to elicit E_max

What ties drug binding to the end effect?

Is coupling usually simple or complex?

when an E_max is reached but there are still receptors left unbinded

maximal effect elicited by activation of relatively few receptors because the response initiated by an individual drug-receptor binding event persists longer than the binding event itself.

The receptor is available for drug binding, however, intermediate activation is taken place; this means downstream signaling ________

Spare receptors dramatically influence K_d. T/F?

If your EC₅₀ is 10 and you have 10 receptors, what is your K_d?

Partial agonists are ______ couplers

How can we inhibit the response of a full agonist clinically?

-receptors can be in active form (R_a) or inactive form (R_i)

-shift equilibrium to R_i

-receptors can be in active form (R_a) or inactive form (R_i)

-shift equilibrium to R_a

-block transition to R_a by competing for orthosteric site

-can be overcome with increasing [agonist], thereby shifting potency (EC₅₀)

-block transition to R_a by binding to an allosteric site

-cannot be overcame by increased [agonist], thereby shifting efficacy (E_max)

All drugs are either agonists or antagonists. T/F

Why aren't EC50 and Kd always the same?

______ is what ties drug binding to the end effect

If you have 10 receptors, K_d is 10.

If no spare receptors exist,

-receptors that produce a lower effect at full receptor occupancy

Partial agonists can competitively inhibit the responses of a full agonist. True or false?

What is antagonists role in R_a and R_i equilibrium?

Competitive antagonists ________ to Ra by competing for the ________

Noncompetitive antagonists _______ to Ra by binding to an __________

Which type of antagonists can be overcame with increasing agonist? Which cannot?

a. competitive; uncompetitive

b. noncompetitive; competitive

c. competitive; noncompetitive

-this measuring factor utilizes the ratio of a known concentration of antagonist and compares it to an agonist without antagonist present vs with antagonist present.

-defines the strength of competitive antagonist

All drugs are either agonist or antagonist. True or false?

Which type of receptors don't respond to typical ligand binding interactions?