Class notes
Medical pharmacology lecture 1-8 notes (2022)
- Course
- Institution
The notes include elaborate explanations of all lectures except the last lecture (lecture 9) which is about chapter 12.
[Show more]
Seller
Follow
obblub
Reviews received
Content preview
Lecture 1 – introduction to pharmacologyPharmacology = explanation of action of pharmaca in the human (or animal) body (what drugs do
and how they do it)
- Pharmaca = biologically active substances
o It is a chemical that is usually used to treat disease. But it can also mean other stuff
such as toxic compounds.
o Toxicology = is a subdiscipline of pharmacology
- Medicine = pharmacon (‘drug’) specifically applied for therapy
o They intended to have a selective action but this ideal is seldom achieved.
▪ There is always a risk of adverse (side) effects as well as a benefit connected
with using any drug --> toxic effects. This is why selective action is usually not
always achieved.
▪ Therefore knowledge of pharmacology is needed for using drugs effectively
in therapy.
- Two main areas of investigation into the action of pharmaca
o Pharmacodynamics = “What does the drug do with the body”
o Pharmacokinetics = “What does the body do with the drug”
Pharmacotherapy = applied pharmacology Use of knowledge and insights gained from
pharmacology for the treatment of diseased humans in a responsible, effective and safe manner.
- Each pharmaca has:
o Minimum toxic concentration
o Therapeutic window
o Minimum effective concentration
- There is a direct relationship between
concentration of drug in blood plasm and
its therapeutic effects.
o The concentration in blood plasm
(Cp) has to be in between the
minimum toxic concentration and
Minimum effective concentration
- Primary effect = effect(s) for which the compound is administered
- Side effect = adverse/unwanted effect(s)
o The distinction between primary and side effect is determined by the aim for which
the medicine is administered
▪ I.e. acetylsalicylic acid (aspirin) can be used as a pain killer or against blood
clotting.
- Placebo = a preparation without any pharmacologically active substance
o It may have a therapeutic effect
o The expectation(s) of the patient determine the strength of the placebo effect
o Randomized, placebo-controlled clinical trials = The contribution of the placebo
effect to the overall effects of a drug are investigated in this
- Nocebo = a placebo with unwanted effects (side effects)
, o Nausea = the most common nocebo effect when taking in oral medication even
though the medication does not have this side effect
Phases of making drug:
1. Discovery: takes 2-5 years
2. Development: takes 5-9 years
▪ Phase 1: safety exposure
▪ Phase 2: Efficacy and dose selection
▪ Phase 3: Registration trials
▪ Phase 4: Post approval regulation = after the approval of use they still have
to check how it is going and what the side effects are
Lecture 2 – PD
Pharmacodynamics = what does the drug do to the body
The 4 levels of drug action
1. System level effects = an effect on system function (a system in a body: organs,
cardiovascular system)
o I.e. Blood pressure medication on the system
o But it does not say anything about how to make a better medication
2. Tissue level = effect on tissue function
o i.e. looking at the heart tissue or metabolic activity
3. Cellular level = looking at transduction metabolisms --> the biochemicals linked to drug
target
o I.e. looking at amount of cyclic AMP after giving the drug
4. Molecular level = establish interaction of drug with the molecular targets
o Molecular targets = proteins most of the times --> the drug target
o You can now see what the compound does and interferes with in the body and
develop a better drug --> pharmacodynamics
Molecular level = fourth level and consists of:
Drug targets can be (so drugs can interact with: ) =
- Receptors:
o 2 main groups of drug:
1. Agonist: drug binds to receptor and changes the conformation and
activates thereby the receptors --> has effect on the cell in which this
happens and activates or deactivates transduction mechanisms:
o Enzyme is being activated or inhibited
o Ion channels modulation --> open up or close
o DNA transcription changes
2. Antagonist: drug bind to receptor but conformation does not change of
the receptor
o Does not has effect
o Does have a biological effect
▪ It prevents the binding of endogenous mediators to
the receptor
, - Ion channels as drug targets
o Ion channel = a hole in the membrane through which ions can pass (pores). The hole
is formed by insertions of proteins
▪ They can be either opened or closed
1. Ion channel blockers = permeation is blocked of the ions from inside to
outside of other way around
2. Modulators = they modulate by binding to the protein --> change the
probability of the channel being open of closed
- Enzymes
o They catalyze reactions = turn a substrate into a product
1. Enzyme inhibitors = normal reaction is inhibited
2. Drug that act as false substrate = they look like the substrate and can
bind to the enzyme --> the enzyme thinks it is a normal substrate and
turns it into a product
o So the normal reaction is inhibited AND also a new product is
being formed --> this new product might have a biological
effect that the body did not want.
3. Pro-drug = are inactive by themselves --> recognized by enzyme -->
activates the drug
o They only activate in specific places (organs) that express the
specific enzyme
o i.e. treating Parkinson’s disease with levodopa = tyrosine
hydroxylase (enzyme) activates this drug --> dopamine
- Carrier molecules = transporters
o They transport a substrate form one side of the membrane to the other side of the
membrane
1. Inhibitor = bind to the binding site of the transporter --> the compound
cannot be transported anymore
2. False substrate = accumulation of an abnormal compound happens
because the substrate is carried by the transporter
Types of receptors on which and (ant)agonist can bind = all receptors have different time scales in
which the reaction happens
1. Type 1: Ligand-gated ion channels = ionotropic receptors
o These are present in cell membranes
o They are proteins, so a receptor, and have also ion channels inside the protein
structure
▪ So they are: receptors and ion channels
o When something binds on the binding domain --> the ion channels open up or close
o I.e. nicotinic Ach receptor
receptors
▪ Very fast = depolarization
or hyperpolarization (ms)
, 2. Type 2: G-protein-coupled receptors = metabotropic receptors
o Expressed inside membranes
o When drug binds to binding domain --> G-proteins are directed towards the
receptors --> activity is altered of second messenger proteins (cyclic AMP for
example)
o Takes a bit more time for the effect to be seen --> protein phosphorylation takes
time
▪ i.e. muscarinic ACH receptors
3. Type 3: Kinase-linked receptors
o Are proteins in membranes + have a catalytic domain
o When drug bind to binding domain --> kinase activity is altered (blocked or
stimulated)
o Receptors is also an enzyme --> leads immediately to alteration of protein
phosphorylation --> gene transcription which takes a lot of time
▪ i.e. cytokine receptors --> takes hours
▪ I.e. insulin
4. Type 4: nuclear receptors
o Located = in cell nucleus membrane
▪ Inactive = in cytosol
▪ Binding of ligand --> they move in cell nucleus --> bind to DNA parts -->
modify DNA transcription
o So they are: transcription factors
▪ All type 4 receptors are transcription factors but not all transcription factors
are type 4 receptors
o I.e. oestrogen receptors
▪ The activation takes time and gene transcription takes time --> takes hours
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller obblub. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $14.62. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
75323 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now