Other
Lecture notes psychopharmacology
- Course
- Institution
- Book
This contains extensive elaborations of the lectures of the course Psychopharmacology . Written in English (according to the language in which lectures have been given.
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
More summaries for
-
UU Psychopharmacology 2024 - All studyquestions + answers!!
-
Psychopharmacology overzicht neurotransmitters en hun werking
-
Summary of psychopharmacology UU
Seller
Followhannahvanrhoon
Reviews received
Content preview
Lectures psychopharmacologyLecture 1 – introduction and overview
• Drug/pharmacon: an administered substance that influences physiological processes
o Sometimes also body’s own substances
o No pharmacon if it’s primarily a nutrient (metabolizes and other purposes)
• Psychoactive substances: influence processes in the brain and hence behaviour, cognition,
affect (emotions)
o Different purposes:
▪ Therapeutic: cure a disease or alleviate some symptoms
▪ Recreational purpose
• Pharmacology: studies the influence of substances on biological processes
• Psychopharmacology: focusses on substances that influence the brain, effects on behaviour,
cognition and affect
o Affects the brain
• You use in daily life lots of psychopharmacological influences
o Tea, coffee, energy, beer, smoke, recreational drugs
• Interest: clinical applications, often quite a bit of media attention for new psychoactive drugs
or certain adverse reactions that drugs may have
o How does this work? Why do theses substances do what they do?
o Some prescription drugs are used for recreational purpose (Ritalin —> ADHD)
• Interest: development of future applications
o Cannabinoid system for extinction of fear in the brain???
• Pharmacokinetics: how does a substance move through the body?
o How do you administer it?
o How is it absorbed? In fat? Does it reach the blood easily? Is it easily degraded in the
body?
o May be important for some medication.
• Pharmacodynamics: what does the substance do to the body once it’s in there?
o To what receptors does the substance bind? If it binds, what kind of effect does it
have there?
Neurotransmitters (basics etc.)
• Brain consists of all kinds of cells
• Neurons ‘talk’ to each other
• Neuron emits an action potential
o Synaps at the end of the axon can be activated, what happens there is a chemical that
interacts
• Neurotransmitters is released in the synaptic cleft
o In order to be released, it has to be synthesized (has to be present there, or
generated)
o Has to be released
• After release there is a form of degradation to end the action on the post-synaptic neuron
• Neurotransmitters work on neurons via receptors
o Complex protein chains
• What is the most typical receptor?
o Either presynaptic, postsynaptic or auto-receptor?
, o Postsynaptic! Effects of neurotransmission depend primarily on post-synaptic
receptor
• What is not a drug target to influence the functioning of neuron?
o Ether receptor activation, metabolite excretion, reuptake blockade, enzyme
modulation, all of the above are possible targets?
o Metabolite excretion! Metabolites are the parts in which a molecule is dissembled
before it is excreted, don’t have a psychoactive effect
• Neurotransmission: drugs activate a certain receptor
o Some kinds of receptor have control in ion-channels (changes in the membrane)
o Some receptors have an effect on the membrane potential, but indirectly through
another route
• Nerves are surrounded by membranes, and have an intercellular space
o Difference between within and outside the nerve cell divided by this membrane
o Potential difference between inside and outside (+/- 70 mV)
o Neurotransmitters act on neurons via receptors
o Effect: small change with respect to the resting potential (EPSP/IPSP) that can add up
to the threshold for an action potential
o EPSP: excitatory post-synaptic potentials
o IPSP: inhibitory post-synaptic potentials
• Inhibitory receptors increase the potential differences
• Excitatory receptors reduce the potential difference to zero, increases the chances of an AP
being generated
• Building blocks for neurotransmitters, some of them typically come from diets
• Tyrosine —> DOPA —> dopamine
o When the neurotransmitters have been synthesized they can enter little vessels which
allow the release of the NT into the synaptic cleft
• NT have an effect on a relatively low amount of neurons in the brain
o Norepinephrine, dopamine, serotonin (only a small proportion)
o Relatively specific targets
• Other NT’s are used by lots of different neurons in the brain
o Inhibitory neurotransmitter GABA, excitatory neurotransmitter glutamate
o Used in about 50% of the synapses
o Also: endocannabinoid is present in many synapses
• Neurotransmitters have been implicated receptors in many synapses
o GABA: alcohol, sedatives, anxiolytics
o GLU, NMDA: epilepsy, Huntington, aids, dementia, schizophrenia
o Typically a problem of specificity of drug targets
Specific neurotransmitters
• Neurotransmitters come from precursors: substances that are needed to construct the
neurotransmitter from
• Monoamines: precursor is tyrosine, essential amino acid (through food!)
o Catecholamine, DA, NE, E
▪ Tyrosine —> dopa —> dopamine —> norepinephrine —> epinephrine
o Serotonine (5-HT), precursors is tryptophan
• Amino acid: glutamate, GABA, precursor is glucose
• Acetylcholine (ACh): precursors is choline/lecithin
• Peptides: oxytocin, endorphins, precursor = many different amino acids
,Neurotransmission: types of receptors
• Post-synaptic/axo-dendritic: receptors that are activated by a combination of an axon and a
dendrite
• Presynaptic receptors, most important is the auto-receptor
o Sits quite close to the synaps, can detect neurotransmission or release of
neurotransmitter from its own axon terminal
o Typically has a feedback role in which, neurotransmitter release will be ended
• Heteroreceptor: receptor on presynaptic neuron that reacts to input from another neuron
o Modulates synaps from another neuron
• Auto-receptors on other locations on the neuron, e.d. Dendrite, soma or other parts
• Activation of all of the receptors can have different implication on modification of
neurotransmission
Types of neurotransmission
• Synaptic axo-dendritic receptor
• Retrograde transmission: case in cannabinoid system
o Post-synaptic neuron releases endo-cannabinoids that active receptors on the pre-
synaptic neuron and can also end neurotransmission
• Non-synaptic diffusion: not really transmission between pre-synaptic and post-synaptic cell,
but receptors on other parts of the receptor can be activated
• Neuromodulators: do not active receptors directly, but modify receptors that when
neurotransmitter binds, properties of receptors are different
o Benzodiazepine
• Neurohormones: released in the blood, not released in synaptic communication. Can also
activate receptors on distant sides
Specific/most important neurotransmitters in the brain
Afkorting Substance Receptors Functions
ACh Acetylcholine Muscarinic (M1-M5), Memory, sensory
nicotinic (Nn, Nm) processes, motor
coordination,
parasympathetic ANS
NE Norepinephrine Alpha1-2, Beta1-2-3 CNS sensory
processes, cerebellum,
sleep, mood, learning,
memory, arousal,
sympathetic ANS
DA Dopamine D1-D5 (families: D1, Motor coordination,
D2) reinforcement, smell,
mood, concentration,
hormone regulations
5-HT Serotonin 18, divided in families Emotion, mood,
5-HT1-5-HT8 appetite, sleep, pain,
hallucinations, reflexes
GLu Glutamate NMDA, quisqualate, LTP, memory,
kainate excitation in
central/peripheral NS
, GABA Gamma amino-butyric GABAa, GABAb Inhibition in CNS
acid
VAR Peptide E.g. hormone E.g. social behavior,
pain, etc.
• Different subtypes! For this course you don’t need to know all different types of all different
receptors
o Only the important different subtypes (mentioned explicitly)
Specific neurotransmitters (NT): where to? Ending NT activity
• Neurotransmission has to be ended in order for the post-synaptic neuron to stop being
activated
• Different neurotransmitters have different ways in how their transmission is being degraded
• Combinations of degradations (metabolism) in synaps and reuptake within the cell
• For example: ACh is degraded outside of the cell, metabolites (parts that its broken down into)
are taken back up in the cell to be reused
• 5-HT: reuptake within the cell, broken down inside the cell (intracellular degradations)
• Peptides: outside of cell
• ACH: extracellular degradation
• Catecholamine: NE & DA, neurotransmission mostly ended by reuptake in the cell. 5%
extracellular by COMT enzyme (catechol-O-methyltransferase) in PFC. Makes it interesting
target for psychiatric disorders
• Amino-acids GLU & GABA: can be transferred into each other, have a very similar structure.
Degradation inside the cell. Glu is precursor for GABA
• What is NOT a precursor for noradrenaline?
o Either tyrosine, tryptophan, dopamine
o Tryptophan! Precursor for serotonin
• From modulation of which neurotransmitter do you expect the most specifically localized
effects in the brain?
o Either glutamate, GABA, dopamine
o Dopamine!
Specific neurotransmitters: anatomical origin NE/5-HT tracks
• NE & 5-HT origins in midbrain & brainstem
o NE: cell bodies in locus coerulus, other parts in pons and brain stem
o 5-HT: cell nuclei in raphe nuclei
• Relatively few cells, but many influential projections to entire cortex
Points of engagement around the synapse
• Modulate presence of precursor or activity of enzyme that synthesize neurotransmitters
• Influence of uptake in and release from vesicles
• Modify post-synaptic receptors
o Blocking (neurotransmission no longer has an effect)
o Administer drug that activates receptor as if neurotransmitter has bound to it
o Different ways of doing it
o Can both be done on pre- and post-synaptic receptors
• Drugs sometimes target how neurotransmission is being ended
o Blocking reuptake, often used mechanism
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 hannahvanrhoon. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $5.34. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
53068 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now