test 3

Pharmacodynamics

The study of what drugs do to the body and their interactions with molecular targets.

Agonists

Drugs that elicit responses by mimicking endogenous molecules.

Antagonists

Drugs that inhibit responses and are unable to elicit a response on their own.

Efficacy

The ability of a drug to activate a receptor and elicit a maximum response.

Potency

The concentration of a drug required to elicit a response.

Concentration Occupancy Curve

Measures affinity based on the proportion of a receptor occupied by a drug.

Concentration Response Curve

Measures the observed effect of a drug as a consequence of binding.

Full Agonists

Agonists that activate receptors with maximum efficacy.

Partial Agonists

Agonists with low intrinsic activity that can also act as antagonists by preventing full agonists from binding.

Competitive Antagonism

Antagonist and agonist bind to the same active site, preventing the action of the agonist.

$K_D$ (Dissociation Constant)

A measure of the propensity of a compound to dissociate from its receptor.

$K_B$ (for Antagonists)

A constant representing the binding affinity of an antagonist for its receptor.

$pA_2$

The negative logarithm of the concentration of antagonist required to cause a twofold rightward shift of the agonist concentration curve.

Shield Plot

An analytical plot used to quantify antagonist potency in competitive antagonism.

Non-Competitive Antagonism

Antagonism that occurs without binding at the same active site as the agonist, leading to a reduction in maximum efficacy.

Reversible Characteristics

Characteristic of competitive antagonism where the effect can be overcome by increasing agonist concentration.

Allosteric Modulation

The interaction that changes the affinity or activation state of a receptor at a different binding site.

Functional Antagonists

Two agonists acting on different receptors to produce equal and opposite effects.

Clinical Efficacy

The effectiveness of a drug in achieving a desired therapeutic outcome.

Narrow Therapeutic Window

When the same molecular target produces both a desired therapeutic effect and an undesired toxic effect.

High-Affinity Competitive Antagonists

Antagonists with slow dissociation that can act as irreversible by reducing available receptors.

Dependent Effects of Antagonists

Effects that can be observed as shifts in the agonist concentration-response curve.

Desired vs. Undesired Effects

The distinction between the therapeutic effect targeted by a drug and its potential toxic effects.

Pathway Inhibition

Inhibition of signaling pathways involved in the drug's action.

Receptor

A molecular target that interacts with a drug to elicit physiological effects.

Ion Channels

Biomolecules that can be targeted by drugs to influence cellular ion flow.

Efficacy vs. Affinity

Efficacy refers to the ability to elicit a response, while affinity describes how tightly a drug binds to a receptor.

Therapeutic Benefit

The positive outcomes achieved by the use of a drug.

Toxicity

Adverse effects caused by a drug that can lead to harmful outcomes.

Dose-Response Relationship

The relationship between the amount of drug administered and the resulting effect.

Endogenous Molecules

Naturally occurring substances in the body that agonists mimic.

Receptor Binding Sites

Specific areas on a receptor molecule to which drugs bind.

Concentration Dynamics

Changes in drug concentration that affect its pharmacological effect.

Maximal Efficacy

The maximum response an agonist can produce at a given receptor.

Pharmacokinetics

The study of how drugs move through the body over time.