week 1 lecture 1: introduction to pharmacology

• drugs are not always used to treat conditions
• give an example of when drugs are administered, but not to treat conditions

  antibiotics after given after surgery to prevent infections
• what term is used to describe prevention against disease?


  prophylaxis
• give examples of prophylaxis 


  washing hands, cleaning surfaces, consuming antibiotics
• what are the aims of a good drug?


  to be safe and to be effective
• what are the two main domains considered when studying drugs?

  1. pharmacodynamics
  2. pharmacokinetics
• what is pharmacodynamics?


  the action of drugs on the body, and the effects they produce
• what specific things are considered in pharmacodynamics? 


  the mechanism of action, specific receptors the drug binds to, and what effect drugs have on cells
• what is pharmacokinetics?


  the study of how drugs are absorbed, distributed, metabolized, and excreted by the body
• what is pharmacokinetics in simple terms?


  the action of the body on the drug
• pharmacogenomics is much more recently developed
• what is pharmacogenomics?

  how genes affect a person's response to drugs, and how genes impact the effect of drugs
• pharmacogenomics is important in personalised medicine
• how is pharmacodynamics plotted?

  drug concentration (mM) on the x axis, and the effect of the drug on the y axis
• in an instance where the effect of a drug (i.e., muscle contraction) is measured against drug concentration, what would explain a plateau?


  the muscle cannot contract past a certain point, no matter how increased the drug concentration is
• plateaus occur at high concentrations
• what term is used to describe the plateau in a pharmacodynamics plot?


  100% effect
• the effect of a drug at 50% in a pharmacodynamics plot (i.e., dosage at 50%) gives a measure of the potency of a drug
• therapeutic/toxic action is dependent on the amount of drug at the site of action
• the majority of drugs bind to receptors, but they can also block them
• why do some drugs block the reuptake of neurotransmitters?


  to make them accumulate in the synaptic cleft
• what are agonist drugs?


  drugs that stimulate specific receptors that they bind to
• what happens after an agonist binds to a receptor?


  mimics the same effect of the endogenous molecules that would normally act on the receptor
• what does endogenous mean?


  originating from within an organism
• how does adrenaline work during the fight-or-flight response


  epinephrine (adrenaline) binds to beta-adrenergic receptors, which increases the heart rate
• adrenergic agonists act as agonists to adrenaline by binding to the same beta-adrenergic receptors and producing the same response (increased heart rate)
• G-protein coupled receptors are activated by small molecules that bind to it, and activate the G-protein
• give an example of something a G-protein can do once activated


  stimulate an enzyme and produce a certain response
• adenylate cyclase transforms ATP into cAMP
• G-protein commonly stimulates adenylate cyclase, increasing cAMP, which can open/close channels
• what determines whether an increase in cAMP will open or close channels?


  the type of cell/tissue
• tyrosine kinase is an important mediator of the cell signalling cascade
• tyrosine kinase receptors are still attached to the cell membrane
• tyrosine kinases utilise ATP and become activated via phosphorylation
• once tyrosine kinases are activated, they produce a certain effect (i.e., opening and closing channels)
• tyrosine kinases are enzymes that transfer a phosphate group from ATP to the tyrosine residues of specific proteins inside a cell
• tyrosine kinase functions as an "on" or "off" switch in many cellular functions
• antagonists prevent the effect of endogenous agonists on receptors
• antagonists are usually competitive inhibitors
• antagonists do not elicit biological responses