Karteikarten
PSYC 318- Lecture #1
Karten in diesem Stapel (19)
- 1What does a neurone consist of?15% nucleic acids (DNA, RNA)
50% A.A.
10% lipids (cell membrane)
15% carbohydrates
10% organic molecules - 2Protein Synthesisa) gene = functional unit of a chromosome
b) when a gene is read it is transcribed in the nucleus by RNA polymerase into mRNA
c) mRNA leaves nucleus, attaches it's self to a ribosome, translated into protein (string of A.A.) - 3Cell Basicsa) Neurone classified by location of soma
b) extracts energy from nutrients
c) microtubules = transport of materials in neurone
d) axon terminals release NT after receiving an action potential
e) soma = metabolic centre of a cell - 4Synapses can form between axon terminals and... a) b) c) d)a) dendrites
b) dendritic spines
c) soma
d) other axon terminals - 5Conventional Neurotransmitters99.9% of neurones use either GABA or Glutamate ( in addition to neuropeptides, or neuromodulators )
- 6Conventional Neurotransmitters: Glutamatea) excitatory
b) induces EPSP ( excitatory post-synaptic potentials ) result = depolarization of membrane (& possible an action potential)
c) agonist = seizures
d) antagonist = ketamine, PCP - 7Conventional Neurotransmitters: GABAa) inhibitory
b) Induces IPSPs (inhibitory post synaptic potentials) induces hyper polarization
c) antagonist = seizures
d) agonist = anticonvulsants, muscle relaxants, anesthetics (alcohol, barbiturates, bezodiazapines) - 8Neural IntegrationDef: integration of excitatory and inhibitory potentials on a synapse
a) if several EPSPs are active at the same time; result = action potential
b) if several inhibitory synapses are active at the same time as EPSPs there will be a dec. in size of EPSP, and axon won't fire - 9Conventional Neurotransmitters: neuromodulatorsa) also classical neurotransmitters ( like GABA & Glutamate )
b) called neuromodulators b/c most are glutamate receptors ( not ion channels )
c) diffuse short distances outside the synapse and can influence firing of neighbouring cells
i.e. acetylcholine, serotonin, dopamine, noradrenaline - 10What does a neurone need to use a neurotransmittera) needs: vesicular transporter to concentrate NT into a vesicle
b) sometimes present:
i) biosynthetic enzyme to synthesize NT
ii) uptake transporter in plasma membrane
iii) mechanism for degradation of neurotransmitter - 11Brain Organized Around Chemical Transmission 1. Conventional Neurotransmitters (G&G&neuromodulators)a) made in axon terminals via synthesis
b) made is SSV dock close to site of Ca2+ entry
c) typically recaptured after secretion
d) usually bind to receptors directly across synapse ( even if NT diffuse it is only very short distances )
e) receptors either:
i) lignin-gated ion channels
ii) g-protein coupled - 12Brain Organized Around Chemical Transmission 2. Neuropeptidea) i.e. opioids
b) few amino acids joined together by peptide bonds
c) secreted from LDCV dock far away from Ca2+
d) synthesized in cell soma (undergo additional transformation while they travel down axon)
e) only released once
f) no synaptic reuse of neuropeptide
g) may diffuse some distance (non synaptic communication)
h) only w. g-coupled protein receptor - 13Brain Organized Around Chemical Transmission 3. Lipid Based Signalling moleculesa) i.e. cannabinoids
b) secretion type: non-vesicular manner
c) secretion location: postsynaptic neurones
d) secreted on demand
e) receptor: g-coupled
f) receptor location: pre-synaptic axon - 14NeuroTransmitters Receptorsa) Ionotropic: fast
b) Metabatropic: slow
i) an be fast: i.e. vision - 15G-protein signallinga) most common receptor
b) activated by: classical NT, neuropeptides, sensory inputs, lipid based signalling
c) effect of a ligand binding to a g-protein receptor is determined by subtype of g-protein & local effectors activated by it
d) example:
i) beta-norepinephrine (beta-adrenergic) coupled to g-protein 'Gs' actives protein adenylate cyclase
ii) alpha-norepinephrine (alpha-adrenergic) receptors activate 'Gi' which inhibit protein adenylate cyclase
iii) conclusion: norepinephrine can activate receptors producing opposite effects - 16Synaptic Plasticitya) factors that influence synaptic strength
i) release of NT from presynaptic terminals
ii) effect of NT binding to post-synaptic terminals - 17NAca) process:
i) reinforcement learning
ii) award seeking
ii) motivation
b) diff. between 2 voles is amount of OXT receptor expression in NAc
c) artificially deriving OXT receptors in NAc of non-monogamous makes them monogamous
d) OXT signalling in NAc, mediator of reinforcement of social interactions - 18OXT #1a) produced: neurones in Hypothalamus
b) released: neuropeptide & hormone (pituitary -> bloodstream)
c) diff in OXT receptor gene = maladaptive social behaviour (aggression) - 19OXT #2a) most rodents fe OXT receptors in NAc vs. voles
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- Psychology Karteikarten am PSYC 318- Lecture #1, erstellt von Pascale Bockelmann am 11/01/2017.
- Erstellt von
- Pascale Bockelmann
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