Pharmacology Chapter 5 Quiz

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a characteristic of partial agonists in relation to full agonists?

They enhance the effects of full agonists.

They are completely ineffective at binding to receptors.

They can produce full agonist effects.

They may cause withdrawal symptoms in opioid-dependent patients. (correct)

What differentiates competitive antagonism from non-competitive antagonism?

Non-competitive antagonists permanently bind to receptors.

Non-competitive antagonism can be overcome by increasing levels of the agonist. (correct)

Only competitive antagonists bind reversibly to receptors.

Competitive antagonism can be overcome by increasing levels of the antagonist.

What results from the continuous administration of antagonists?

Decreased production of endogenous ligands.

Enhanced agonist efficacy.

Reduced receptor sensitivity.

Up-regulation of target receptors. (correct)

What is the primary effect of an inverse agonist on receptor activity?

It inhibits basal activity of the receptor. (C) Signup and view all the answers

Which of the following compounds is an example of a competitive antagonist?

Flumazenil (A), Vecuronium (C), Naloxone (D) Signup and view all the answers

What is the primary effect of a full agonist on a receptor?

Produces maximal response from receptor (B) Signup and view all the answers

What happens to target receptors with continuous administration of an agonist?

Receptors undergo down-regulation (A) Signup and view all the answers

Which type of agonist produces a weaker effect than a full agonist?

Partial agonist (C) Signup and view all the answers

What type of bonding is primarily involved with agonists and receptor interactions?

Ionic, hydrogen, and London forces (C) Signup and view all the answers

Which of the following statements best describes a partial agonist?

Also known as a mixed agonist-antagonist (D) Signup and view all the answers

What is the primary focus of pharmacogenetics?

Genetically determined variations in drug metabolism (C) Signup and view all the answers

Which aspect does pharmacogenomics emphasize within drug response?

Variations in genome affecting drug metabolism and targets (C) Signup and view all the answers

What major factor does population variability in therapeutics consider?

Patient age and body weight (B) Signup and view all the answers

What type of variation does polymorphism refer to?

DNA sequence variation that may affect drug pathways (A) Signup and view all the answers

Which of the following drugs utilizes genetic-based response algorithms?

Clopidogrel (C) Signup and view all the answers

How do CYP450 isoenzymes relate to pharmacogenetics?

They exhibit variable enzymatic activities influencing drug processing (B) Signup and view all the answers

What is the significance of understanding individual drug response in pharmacodynamics?

It directly influences the efficacy of a medication (A) Signup and view all the answers

Which of the following populations does population variability NOT typically account for?

Patients from urban areas only (D) Signup and view all the answers

What is the primary goal of pharmacology in the context of anesthesia?

To treat pain and prevent complications (D) Signup and view all the answers

Which of the following best describes pharmacodynamics?

The relationship between effect site concentration and clinical effects (B) Signup and view all the answers

What role do biophysics play in pharmacodynamics?

Defining the effect site where the drug engages with its receptor (A) Signup and view all the answers

How does oxygen and carbon dioxide move through cell membranes?

By simple diffusion across the lipid bilayer (C) Signup and view all the answers

What defines the effect site concentration in pharmacodynamics?

The location where the drug binds to its receptor (B) Signup and view all the answers

Which statement regarding ion channels, receptors, and enzymes is accurate?

They interact specifically with drugs to produce biological effects (B) Signup and view all the answers

In pharmacology, what is the primary focus of pharmacokinetics?

The body’s action on a drug, including absorption, distribution, metabolism, and excretion (C) Signup and view all the answers

What is the composition of the cell membrane?

A phospholipid bilayer with embedded proteins (B) Signup and view all the answers

What effect does increased adipose tissue have on drug distribution in older adults?

Expanded volume of distribution for lipid-soluble drugs. (C) Signup and view all the answers

How does aging affect cardiovascular responses to drugs?

Reduced or exaggerated responses to cardiac medications. (B) Signup and view all the answers

What is a primary alteration in pharmacology for neonates compared to adults?

Lower plasma concentrations of water-soluble drugs. (D) Signup and view all the answers

Which change in respiratory function in older adults increases risks associated with drug use?

Diminished sensitivity to protective airway reflexes. (A) Signup and view all the answers

What impact does reduced renal mass have on drug metabolism in older patients?

Impaired drug excretion and elimination. (C) Signup and view all the answers

What primarily affects the dosing of lipophilic drugs in infants?

Increased total body water. (A) Signup and view all the answers

What role do blood-brain barrier changes play in older adults?

Increased CNS sensitivity to anesthetics and opioids. (A) Signup and view all the answers

What is a consequence of polypharmacy in older adults?

Increased risk of adverse effects due to drug interactions. (B) Signup and view all the answers

What impact does diminished muscle mass have on drug pharmacokinetics in older adults?

Limited reservoir capacity affecting drug distribution. (C) Signup and view all the answers

How does altered cellular response in older adults affect drug dosing?

Causes dose-related adverse effects. (D) Signup and view all the answers

What effect does general anesthesia have on drug metabolism?

It can delay emergence from anesthesia. (A) Signup and view all the answers

What is the primary change in the neonatal nervous system that impacts anesthetic management?

Rapidly maturing central nervous system. (C) Signup and view all the answers

Which factor increases the risk of postoperative nausea and vomiting in pediatric patients?

Prolonged CNS effects of anesthetics. (B) Signup and view all the answers

What contributes to the differences in anesthetic drug responses between sexes?

Hormonal differences. (C) Signup and view all the answers

How does immature renal function affect drug metabolism in neonates?

It reduces renal excretion of unchanged drugs. (A) Signup and view all the answers

What is a significant change in the respiratory system of pregnant women that affects anesthesia?

Increased minute ventilation. (A) Signup and view all the answers

What challenge does the immature blood-brain barrier in neonates present?

Higher risk of CNS drug toxicity. (A) Signup and view all the answers

How does altered hepatic function in pregnancy influence anesthetic considerations?

Potential changes in drug metabolism and duration of action. (C) Signup and view all the answers

What is true regarding the musculoskeletal characteristics of neonates?

There is a gradual increase in muscle mass. (C) Signup and view all the answers

What increases the total body water in pregnant patients, affecting drug distribution?

Increased blood volume. (D) Signup and view all the answers

What risk is associated with the use of systemic opioids during pregnancy?

Potential fetal effects. (A) Signup and view all the answers

Which factor contributes to the higher risk of adverse outcomes in anesthetic management of infants?

Impaired renal and hepatic function. (A) Signup and view all the answers

What physiological change affects the doses required for anesthetic drugs during pregnancy?

Increased sensitivity to anesthetic agents. (D) Signup and view all the answers

Study Notes

Introduction to Pharmacology: Pharmacodynamics

Goal of pharmacology is to prevent, cure, or control disease
Anesthesia aims to manage physiologic changes
This includes sedation, general anesthesia, amnesia, pain treatment, relaxation, and prevention of complications
Safety is a key concern in pharmacology

Pharmacodynamics

Study of what the body does to a drug
Examines the relationship between effect site concentration and clinical effects
- A specific effect site (biophase) is where the drug interacts with a receptor.

Pharmacology (General)

Pharmacodynamics
- The effect a drug has on the body.
Pharmacobiophasics
- The specific area of effect or site, where drugs interact with receptors.
Pharmacokinetics
- What the body does to the drug.
- How the body absorbs, distributes, metabolizes, and eliminates a drug.

Physiology Review

Cell membrane structure
- Bi-layer
- Mostly impermeable to ions and glucose
- Contains channels, receptors, and enzymes.
Mechanism for oxygen and carbon dioxide movement across cell membranes
Sodium-potassium ATPase
- Function: moves sodium and potassium ions across the membrane.
- Number of Na+ ions moved (out).
- Number of K+ ions moved (in).
Endoplasmic reticulum and its role in protein, lipids, and carbohydrate metabolism.
Sarcoplasmic reticulum role in muscle cell function.

The Action Potential

Action potential graph
- Motor neuron, skeletal muscle, cardiac ventricle
- Time scales (2ms, 5ms, and 200ms)
Resting membrane potential
- Slightly polarized at -70 mV
- ICF is relatively negative compared to ECF

Neuronal Action Potential

Stimulus (e.g., change in nearby membrane potential) initiates the process.
Threshold at -55 mV when Na+ voltage-gated channels open
Membrane potential reaches +30 mV, Na+ channels close= inactivation
K+ voltage-gated channels open as a delayed response
Action potentials from three cell types are shown.

Action Potential Abnormalities

Hypocalcemia
- Prevents Na+ channels from closing between APs
- Can cause sustained repetitive firing.
Hypercalcemia
- Decreases cell membrane permeability to Na
- Results in decreased excitability of the membrane
Hypokalemia
- Negative effect on membrane excitability
Sodium
- Channel blockade affects AP generation.
- Results in decreased contractility and altered cardiac conduction.

The Synapse

Transmission from pre-synaptic membrane to post-synaptic membrane
Neurotransmitter vesicles release neurotransmitters across a cleft
Reuptake pumps and voltage-gated Ca channels are involved
Receives afferent action potential

Synapse: Modulation and Fatigue

Changes in synaptic function
Synaptic signaling involves membrane potentials influencing depolarization and stimulus response.
Interval is 0.3–0.5 ms for neurotransmitter release, diffusion, binding, ion flow.
Fatigue occurs in excitatory synapses during repetitive stimulation.
Reduced post-synaptic response occurs, possibly due to neurotransmitter depletion.

Neuronal Responsiveness

Changes in pH
- Alkalosis increases excitability
- Acidosis decreases excitability
Changes in PaO2
- Hypoxia decreases excitability
Other factors such as changes in pH and PO2 affect neuronal excitability.

Receptor Pharmacology

Receptors bind endogenous chemical or drug
Properties: sensitivity, selectivity, specificity, and locations
Receptors are located in the membrane or inside the cell

The Receptor

Administration leads to onset of effect
Molecular orientation and receptor attachment rely on hydrophobic bonding.
Conformational changes lead to cellular activity or tissue responses.
Acceptors (e.g., albumin, alpha1 acid glycoprotein, beta-globulin) bind drugs, potentially reducing free drug concentration.

Chemistry Applications

Dipole-dipole interactions are important for several biological processes.
Hydrogen bonds play a crucial role in receptor pharmacology.
Other specific chemical mechanisms are relevant.

Stereochemistry & Chirality

Stereochemistry involves the 3D molecular structure.
Chirality relates to 3D asymmetry in molecules.
Enantiomers are mirror images that cannot be superimposed.

Receptor States

Varying receptor conformations influence ligand binding and affect physiologic effects.

Receptor Actions

Receptors receive and transduce signals following ligand binding.
Signal transduction pathways involve signal amplification and integration.

Receptor Types

G-protein-coupled receptors
Ligand-gated ion channels
Voltage-gated ion channels
Kinase-linked receptors
Nuclear receptors

G Protein-Coupled Receptor

Comprises a receptor protein and G-proteins like α, β, and γ.
Activation involves extracellular ligand binding, conformational change, GDP-GTP exchange, and interaction with effector proteins.
Generates downstream events to affect response in cells.

Ion Channels

Flow of ions driven by concentration gradients
Different types include voltage-gated, ligand-gated, and mechanically gated channels.
Na+, K+, Ca2+, and Cl− channels play crucial roles in cellular function.

Ligand-Gated Ion Channels

Facilitate fast synaptic transmission between cells.
Ligand-receptor binding causes conformational changes, opening or closing channels, affecting ion flow.
Excitatory channels include acetylcholine, glutamate NMDA, AMPA, kainate, and serotonin receptors.
Inhibitory channels include GABA and glycine receptors.

Voltage-Gated Ion Channels

Channels change conformation in response to voltage changes across cell membranes.
Involved in nerve impulse conduction and muscle contraction.

Cellular Response

Cellular processes, enzymatic activities, and cell migration, are triggered by different signals and ligand binding.
- Examples: increased/decreased activity, chain reactions, and more.

Cellular Response and Homeostasis

Increased receptor number increases response to the agonist.
Decreased receptor number and sensitivity reduces response to agonist.

Upregulation/Downregulation

Upregulation increases receptor number; downregulation reduces.
Chronic exposure to ligands can result in downregulation.
Examples include drug exposure.

Drug Dose Response

Dose recommendations are based on averages in normal, healthy populations; individualized treatment may be required
Titration is typically needed until the desired therapeutic response
Dose–response curves can be graded or quantal.

Potency vs Efficacy

Potency refers to the drug concentration needed to produce a given effect
Efficacy refers to the maximum effect a drug can produce (y-axis).

Receptor Pharmacology: Agonists, Antagonists

Agonists mimic endogenous ligands.
Antagonists block receptors.
Partial agonists have only part of the maximal effect.
Inverse agonists produce an effect opposite to that of an agonist.

Allosteric Modulator

Binds to an allosteric site on the receptor
Modifies the receptor's response to an agonist.
Distinct from normal agonist binding site

Drug Interactions

Additive effect: sum of effects due to combined use of drugs
Antagonistic effect: one drug blocks the effect of another.
Potentiation: effect of one drug is enhanced by another.

Tachyphylaxis

Response to a given dose decreases with repeated administration
Possible reasons include pharmacokinetic and pharmacodynamic mechanisms
Examples include certain drugs that can cause tachyphylaxis

Quick Review/Trick Review

Review of drug dose-response curve.
Questions to help with understanding potency, safety margins and other related concepts.

Memory Master Knowledge Check

Questions related to different concepts.

Pharmacogenetics and Population Variability

Variations in genetic makeup can affect drug response.
Pharmacogenomics helps identify optimal therapies.
Drugs differ in their metabolic pathways.
- Examples: CYP450 isoenzymes and more

Older Adult/Geriatric Considerations

Changes in blood volume, body composition, and organ function affect drug response in older adults.
These include factors affecting organ function.

Pediatric/Neonatal Considerations

Factors like immature organs and rapidly maturing systems influence responses to drugs in children.
Considerations of body composition, and metabolism affect drug action.

Obstetric Considerations

Pregnant persons have physiological changes.
Including considerations of increased blood volume, altered metabolism, and more.

Sex-Dependent Differences

Hormonal differences and differences in organ function can influence drug responses in males vs females.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge of pharmacology concepts in Chapter 5, focusing on agonists, antagonists, and their effects on receptor activity. This quiz includes questions about partial agonists, competitive and non-competitive antagonism, and inverse agonists. Perfect for students looking to solidify their understanding of drug-receptor interactions.