pharmacology

Question 1

what is a drug?

Answer 1

any substance that breaks about a change in biological function through chemical action

Question 2

what is pharmacology?

Answer 2

the study of substances that interact with living systems via chemical processes

Question 3

what is pharmacodynamics?

Answer 3

the effect of drugs on biological systems

Question 4

what is pharmacokinetics?

Answer 4

the effect of biological systems on drugs

Question 5

what are the 2 types of drug mechanisms?

Answer 5

non-receptor (changing physical chemical properties) and receptor (the majority, receptors, enzymes, carriers etc.)

Question 6

what is a bioassay?

Answer 6

the process by which the activity of the substance is measured on living material

Question 7

what is the dose-response relationship?

Answer 7

concentration of drug at receptor site vs the magnitude of the response

Question 8

what does an agonist do?

Answer 8

binds and activates receptors

Question 9

what does an antagonist do?

Answer 9

binds and causes no activation

Question 10

what is the law of mass action?

Answer 10

rate of reaction is proportional to the product of the concentration of reactants

Question 11

what is the magnitude of response determined by?

Answer 11

the number of drug molecules present, proportion of available receptors occupied by the drug, and rate of drug-receptor complex formation

Question 12

what are the 2 stages of agonist binding?

Answer 12

occupation (drug binds) and activation (receptor changes shape)

Question 13

what is kD equation?

Answer 13

dissociation constant / association constant

Question 14

what is affinity?

Answer 14

the tendency to bind to receptors

Question 15

what is efficacy?

Answer 15

the ability to activate receptors

Question 16

what is potency?

Answer 16

the amount of substance required to be efficacious (reach 50% max efficacy)

Question 17

what are EMax, ED50 and EC50?

Answer 17

maximum efficacy, dose that produces half max effect, and concentration that produces half the max effect

Question 18

what does a competitive antagonist do?

Answer 18

reversibly binds to receptors, has affinity but no efficacy, prevents agonist binding unless agonist concentration increases. decreases potency NOT efficacy

Question 19

what does a non-competitive antagonist do?

Answer 19

decreases potency AND efficacy

Question 20

what is signal transduction?

Answer 20

biochemical mechanisms responsible for transmitting extracellular signals inside the cell. this leads to activation of the target protein

Question 21

what are the steps of signal transduction?

Answer 21

1st messenger travels to cell and binds to receptor (extracellular) and initiates conformational change. the receptor protein stimulates signalling proteins. 2nd messengers amplify signal and bind to additional signalling proteins. the signal is propagated, target proteins are affected and the signal is terminated

Question 22

what is a first messenger?

Answer 22

a small diffusible molecule that can be produced by endocrine mechanisms or locally function

Question 23

what is endocrine signalling?

Answer 23

signalling where endocrine cells release hormones that tact on distant target cells

Question 24

what is paracrine signalling?

Answer 24

a form of cell-cell communication where a cell produces a signal to induce changes in nearby cells (alters their behaviour)

Question 25

what is autocrine signalling?

Answer 25

cell signalling where a cell secretes a hormone or chemical messenger that binds to autocrine receptors on that cell

Question 26

what are cells of primary messenger examples?

Answer 26

peptide and steroid hormones, amino acid derived, omega fats, neurotransmitters and neurohormones

Question 27

what do second messengers do?

Answer 27

initiate cell transduction cascade

Question 28

what are receptors important for?

Answer 28

drug action, specificity, mechanism of action, therapeutic targets, and personalised medicine

Question 29

what are some example drugs and receptors?

Answer 29

cetirizine + histamine h1 (allergen blocker) insulin + insulin receptors (diabetes management)

Question 30

what are the 4 receptor types?

Answer 30

ionotropic (ion channel), metabotropic (GPCRs - cell surface signalling receptors), enzyme linked (single transmembrane protein) and intracellular (transcription factors)

Question 31

what does ADME stand for?

Answer 31

absorption, distribution, metabolism and excretion

Question 32

what is absorption (drugs)?

Answer 32

movement of drug from administration site to blood. mostly passive

Question 33

what is gastric emptying?

Answer 33

time taken for a drug to pass through the stomach

Question 34

what factors affect drug distribution?

Answer 34

regional blood flow, lipid solubility, plasma protein binding

Question 35

where is highest and lowest blood flow?

Answer 35

high: kidney, heart, lungs and brain low: fat and bone

Question 36

what is drug metabolism?

Answer 36

chemical transformations in the body to change drug and reduce lipid solubility or alter biological activity

Question 37

what is bioavailability?

Answer 37

fraction of drug dose that reaches the blood stream in active form

Question 38

what are the phases of drug metabolism?

Answer 38

phase I chemically alters basic structure of a drug. phase II conjugation reactions

Question 39

what are the routes of drug excretion?

Answer 39

kidneys, lungs, liver, faeces, sweat, saliva, tears

Question 40

what are the mechanisms of drug excretion in the kidney?

Answer 40

active tubular secretion, passive tubular reabsorption, glomerular filtration