FINAL REVIEW Flashcards
What converts Serine to Glycine?
Serine transhydroxymethylase
Respiratory - symp coupling contributes to _% of BP
25%
A loss in 2-pore channels lead to shorter or longer time for the rats to be anaesthetised, hence losing sensitivity to it
longer
Most common GABA subunits
a1B2gamma2
Golgi tendon organs encode
Tension
Depolarisation of the outer hair cells alters the physical deformation of the inner hair cells.
Depolarisation of the outer hair cells alters the physical deformation of the inner hair cells.
Prey animals (sheep, cows, horses) have a visual streak, what is that?
Horizontal line of high density detectors that pick up the horizon, looking out for disturbances so they can run away from predators.
RGS (Regulator of G protein Signalling) accelerates?
Hydrolysis of GTP to GDP
PKA - does not only phosphorylate ion channels but also?
Acts as GPCR kinase - phosphorylating GPCR so arrestin will bind to it
List the things PSD95 can bind to (6)
- AMPA
- NMDA receptors
- Neurogilins
- nNOS
- Calcium-calmodulin protein kinase II (CaMKII) (Regulates NMDA and AMPA cycling and implicated in memory formation)
- Shank proteins, indirectly via GKAP -Shanks can also bind directly to neuroligins
PSD93 seems to be involved in nicotinic synapses
PSD93 seems to be involved in nicotinic synapses
Why is the mossy fibre synapse “stronger”?
-More current flows into the dendrite
-The synapses are located close to cell body (less current leakage)
Both lead to greater depolarisation of the neuron
What are the recycling and reserve vesicles tethered to?
Linked by synapsin to Actin filaments
Components of the axonal skeleton (4)
- Microfilaments (actin): 8 nm diameter - most abundant at axon terminus, interacts with spectrin (involved in cell-cell contact)
- Intermediate filaments (neurofilament): 10 nm - used as a marker to differentiate neuron from glia
- Microtubules: 24 nm diameter - made by linear polymerisation of globular proteins
- Spectrin - protein giving shape and support to cell membrane and axonal membrane by forming a lattice underneath the membrane. Globular protein that polymerises and cross-links. Binds to structural proteins such as actin and Ankyrin, and to some integral membrane proteins. It is capable of transmitting extracellular signals (sometimes from adjeacent/contacting cells) to neurofilament and microtubules
Intergrate and fire neurons
- Basis of most neural network models that try to simulate cognitive processes
- Each neuron simply adds the synaptic inputs via some mathematical rule and if a threshold is exceeded an action potential is generated
- The classic version is the McCulloch – Pitts neurons (originally an electronic model).
NL3R451C mice increased GABA function in sensory cortex, increased glutamate function in hippocampus and mimics the KO at some GABA synapses
NL3R451C mice increased GABA function in sensory cortex, increased glutamate function in hippocampus and mimics the KO at some GABA synapses
Microbiome modifies central mood, etc via?
Cytokines, tryptophan metabolites
–Probably also via primary afferent neurons
Tools for study of gut microbiome (3)
- 16S ribosomal RNA sequencing identifying presence of different species
- Metabolomics
- Germ-free mice (mice with no microbiota AT ALL)
Eph/ephrins, semaphorins, tenascin- what are they?
Axon guidance molecules
CSPG (chondroitin sulphite proteoglycans) and Collagen IV
Astroctye ECM
TGFB (transforming growth factor B) activates astrocytes, what happens when you block it?
Nothing - it doesn’t aid in regeneration
Location of neurogenic regions that make stem cells
SVZ and SGZ
1) Subventricular zone of lateral ventricle (goes to olfactory bulb via rostral migratatory stream)
2) Subgranular zone of dentate gyrus of hippocampus (goes to GL layer of hippocamppus)
Inflammatory soup
cytokines, chemokines, metalloproteases
*Chemokines attract stem cells from injury site, affecting recovery
Where does CaCam Kinase II attach to in NMDA?
TAIL
Where is hippocampus found?
Medial temporal lobe and part of cerebral cortex
Function of hippocampus?
Spatial memory (RIGHT SIDE) and consolidation of ST to LT memory
Role of CaCam Kinase II
- Phosphorylates AMPA receptors (increases conductance)
- Phosphorylate PSD-95 (receptor clustering protein) and cause greater clustering of AMPA receptors
- Necessary for structural synaptic plasticity - the formation of new active zones
Ca-activated enzymes in dendrites
Cam kinase II Nitric oxide synthase Phospholipase A2 (-> arachidonic acid) Calmodulin (-> Adenylate cyclase) Protein Kinase C Calpain (proteolytic properties)
Retrograde messengers - able to rapidly diffuse across membranes
Arachidonic acid Nitric oxide Carbon monoxide O2- (superoxide) Cannabinoids
Two phases of LTP
Early (electrical-chemical) - changes regarding transient increase in calcium, phosphorylation, VACC etc.
Late (structural) - increase in N (number of release sites), transcriptional changes involving CREB
Effects of NMDA Stimulation
- Change in probability of vesicle release (This is the earliest phase of LTP)
- Change in size of current produced by each AMPA receptor
- Change in number of AMPA receptors
- Change in the electrical excitability of the dendritic membrane
- Production of a new dendritic spine
BDNF
Important in structural phase, if you activate NMDA long enough, you will get BDNF. During physical and mental exercise, BDNF is released.
Rhythms of the Brain are observed using
Theta 5 - 10 Hz - it disappears when you fall asleep
What is theta rhythm dependent on?
ACh
Where are place cells found?
Medial part of entorhinal cortex, CA3 Pyramidal neurons
Phase precision?
The spiking of a place cell earlier in the phase cycle relative to the theta rhythm of the hippocampus as you move closer to the centre of a space.
