Week 12 / Pharmacology 1 Flashcards
Q: What are the two processes initiated by drug taking?
A: Drug taking initiates two processes:
The action of the drug on the body.
The action of the body on the drug.
Q: What is pharmacology?
A: Pharmacology is the study of the interaction between drugs and the living body.
Q: What is pharmacodynamics?
A: Pharmacodynamics is the study of the effects of drugs on the living body and how these effects are produced.
Q: What is pharmacokinetics?
A: Pharmacokinetics is the study of how the body deals with or handles drugs, including absorption, distribution, metabolism, and excretion.
Q: What is pharmacotherapeutics?
A: Pharmacotherapeutics is the study of the use of drugs in the treatment and prevention of disease.
Q: How do drugs act in the body?
A: Drugs interact with biological systems in ways that mimic or affect the natural chemical messengers or processes of the body.
What are the 2 types of drug action ?
non-specific drug
specific drug
What is non-specific drug action?
Do they have a structure-activity relationship ?
Does it require large doses to produce effects?
A: Non-specific drug action refers to drugs that act in a simple physical or chemical manner, such as antacids, osmotic diuretics, or osmotic laxatives.
These drugs do not have a specific structure-activity relationship
often require large doses to produce an effect.
Q: What is specific drug action?
Do they have a structure-activity relationship ?
Does it require large doses to produce effects?
A: Specific drug action refers to drugs that act in a highly specific manner, interacting with or binding to specific macromolecular or cellular targets in the body, called “receptors.”
Drugs with specific action show a clear-cut structure-activity
relationship
produce biological effects at very low doses.
Q: Can you provide examples of drugs with specific action?
A: Examples of drugs with specific action include phenylephrine, salbutamol, atropine, and digoxin.
Q: What is the drug receptor concept?
A: The drug receptor concept states that most drugs produce their biological effects by interacting with specific macromolecules in the body, called receptors.
Q: What is a receptor?
A: A receptor is the specialized component of a cell or organism that interacts with a drug, initiating the chain of biochemical events that lead to the drug’s observed biological effects.
Q: What are drug receptors made of?
A: Drug receptors are protein or glycoprotein molecules.
Q: Where are most drug receptors located?
A: Most drug receptors are located on the cell membrane. Examples include atenolol, chlorphenamine, cimetidine, and codeine.
Q: Where are some drug receptors located?
A: Some drug receptors are located inside the cell. Examples include receptors for estrogen, testosterone, and vitamin D.
What are the types of Drug targets or Receptors? [4]
Classical’ receptors
Ion channels
Enzymes
Carrier or transport proteins
Q: What are the classical drug receptors?
A: Classical drug receptors are regulatory proteins or binding sites for endogenous or natural chemical messengers, such as neurotransmitters and hormones.
Q: What are examples of drug targets that are ion channels?
A: Examples of drug targets that are ion channels include lidocaine, diazepam, and amiodarone.
Q: What are examples of drug targets that are enzymes?
A: Examples of drug targets that are enzymes include NSAIDs, statins, and ACE inhibitors.
Q: What are examples of drug targets that are carrier or transport proteins?
A: Examples of drug targets that are carrier or transport proteins include digoxin, proton pump inhibitors (PPIs), and selective serotonin reuptake inhibitors (SSRIs).
Q: Why do drugs bind to certain receptors?
the drug’s molecular structure and shape are similar to those of the natural chemical messengers the body produces to target those receptors.
Q: What must occur for a drug to bind to a receptor?
A: There must be a complementary fit between the drug molecule and the binding site on the receptor.
How do drugs interact with receptors?
What is the product of that interaction?
A:
through a reversible chemical reaction.
Drugs and receptors interact to form a drug-receptor (D-R) complex
Q: What principle governs the drug-receptor interaction?
A: The drug-receptor interaction is governed by the Law of Mass Action.
Q: How can drug concentration and biological effect be related?
A: Drug concentration and biological effect can be related to the fraction of receptors occupied by the drug.
Q: What is the ‘Lock and Key’ relationship in drug-receptor interactions?
A: The ‘Lock and Key’ relationship is the basis of the selectivity of drug action, where the drug (the “key”) fits into the receptor (the “lock”) in a specific manner.
Q: What are the two types of selectivity involved in the ‘Lock and Key’ relationship?
A: The two types of selectivity involved are:
Chemical selectivity – the ability of the drug to bind to specific receptors.
Biological or tissue selectivity – the ability of the drug to produce effects in specific tissues or organs.
Q: How do drugs interact with receptors to form a complex?
A: Drugs and receptors interact to form a drug-receptor (D-R) complex through a reversible chemical reaction:
Drug + Receptor ⇌ Drug-Receptor Complex (D-R)
Q: What factors influence the fraction of receptors occupied by a drug?
A: The fraction of receptors occupied by the drug is a function of:
The concentration of the drug in the biophase.
The equilibrium dissociation constant (K) for the drug-receptor complex.
Q: What is the ‘Receptor Occupancy Theory’?
A: The ‘Receptor Occupancy Theory’ states that the drug effect is proportional to the fraction of receptors occupied by the drug.
Q: What occurs when all receptors are occupied by the drug, according to the Receptor Occupancy Theory?
A: When all receptors in the system are occupied by the drug, the maximum drug effect (Eₙ max) occurs.
