Introduction to pharmacology: L15 Flashcards
1
Q
Neuron
- at rest
- AP triggered when
- dendrites are?
- soma is?
A
- negative charge -70
- charge becomes sufficiently positive
- “tree” structures which receive signals from other neurons
- body of the cell
2
Q
- How many neurons in the brain?
2. How many synapses in the cortex?
A
- 100 billion
2. 0.15 quadrillion
3
Q
- How are messages between neurons transferred
2. cell membrane has 2 layers which means
A
- only through neurotransmitters
2. fatty inside layer, fluids and other chemicals like neurotransmitters cannot pass through
4
Q
Receptors
- allow
- 2 types of receptors
A
- the released neurotransmitter to influence the post-synaptic nerve by ‘locking on’ to a receptor
- ion channels and G-protein coupled
5
Q
Ion channels
- act like
- when a neurotransmitter binds to the receptor
- channels are normally
- Overall, Ion channels are
A
- a gate
- causes the gate to open and ions (positive and negatively charged molecules) can flow through
- selective and only allow one or a few types of ions to pass through when open (i.e. calcium ion channel)
- high speed, selective and direct action
6
Q
G protein-coupled receptor
- work through
- when the neurotransmitter binds to the receptor
- this causes either…
- There are…(outcomes)
- this process is
A
- second messengers
- activates a second messenger system
- the channel to open or other things to change within the cell (e.g. DNA being transcribed or new protein being made)
- a huge array of possible outcomes
- very select sequence of events
7
Q
Receptor specificity
- each receptor can generally only
- each receptor has a very
- when a neurotransmitter binds to a receptor this will trigger the same
- what happens to neurotransmitters so they can open a channel
A
- be activated by one neurotransmitter (or a drug designed to mimic neurotransmitter)
- specific function
- event every time (either opening channel or triggering a second messenger event)
- small change in their shape
8
Q
- Neurotransmission definition
2. neuromodulation definition
A
- chemical substance released from a neuron at a synapse (specialised junction) which diffuses into the narrow cleft to affect one or two postsynaptic neurons, a muscle cell or effector cell
- chemical substance released from a neuron in the CNS or PNS that affects groups of neurons or effector cells. Often acts through second messengers and can produce long-lasting effects
9
Q
- Neurotransmission is either…
2. Neuromodulation describes
A
- excitatory or inhibitory and serves rapid (ms), precise, point to point communication
- excitatory = long projection neurons
- inhibitory = short local neurons (dense web around excitatory neurons) - slower (ms-s) processes that alter the subsequent responsiveness of neurons
-> “neurotransmitter” broadly encompasses both
10
Q
- excitatory
- inhibitory
- modulatory
A
- Glutamate
- GABA
- serotonin, dopamine, noradrenaline etc
11
Q
Neuromodulation
- define
- presynaptic
- postsynaptic
- neuromodulation may cause
A
- alternation of nerve activity through targeted delivery of a stimulus (e.g. serotonin)
- alters neurotransmitter release
- alters neurotransmitter action (excitability/firing pattern)
- changes in neural function or structure (e.g. sustained neuromodular activity can drive changes in the brain related to synaptic plasticity)
12
Q
Cycle of neurotransmitters 1-7
A
- synthesis
- release from synaptic vesicles
- binds to receptors
- influence on post synaptic neuron
- broken down by enzymes
(or) - reuptake of transmitter
- formation and storage in synaptic vesicles
13
Q
Psychopharmacology defintion
A
- study of drug induce changes in mood sensation, thinking and behaving
14
Q
Drug action at the receptor
- drugs act by
- Can act as either
A
- mimicking the neurotransmitters or neuromodulators
- Agonists = activating receptor
Antagonists = blocking the receptor, preventing activation
15
Q
synthesis interruption:
Neurotransmitter function can be altered by
A
increasing or decreasing synthesis of the neurotransmitter
