CH4 Flashcards
Behavioural measures are crucial for understanding the ________ basis of behaviour, and drug-induced changes in that behaviour. Developing ______ _____ of psychiatric disorders, and screening newly designed drugs in _______ and ______ pharmaceutical settings
neurochemical, animal models, preclinical, clinical
used with animals and and humans to measure specific physiological, emotional, cognitive, or other psychological processes
test/assay
used to test spatial memory
water maze
used to test for anxiety
elevated plus maze
used to test for rewards
conditioned placed preference
Ideally, tests should tap into similar ______ in humans. However, you can never truly know what an animal is _____, and must infer changes in psychological states based on changes in _______. Typically, multiple tests and ____ procedures are needed to partition complex behaviours into component processes
functions, thinking, behaviour, control
entail some manipulation that causes some cellular/functional change that resembles what is observed in the disease
models
manipulation in models may mimic _______ occurring in the disease (e.g. genetic, environmental), or may be ______ (pharmacological), but still induces a similar behaviour phenotype. For more complex psychiatric disorder, it is near impossible for one model to recapitulate all aspects of the disorder and multiple models are used to re-create different ______.
pathophysiology, artificial, symptoms
seeing what causes the certain symptoms rather than the whole disorder
research domain criteria
surgical brain lesions that permit comparison about the function of a brain area
stereotaxic surgery
broad sucking up of the cortex that permanently destroys tissue
aspiration
the irreversible frying of neurons, which destroys the axon as well as cell bodies
radiofrequency
use of glutamate agonists that overexcites and selectively kills intrinsic neurons in the brain regions; does not affect axons connected to other regions; irreversible
excitotoxic lesion
intracranial infusion of a drug via a cannula to suppress neural activity by use of anaesthetics, or GABA agonists
reversible lesions / inactivation
Intracranial infusions similar to reversible lesions may be used to infuse _____ into specific brain regions to examine where a drug may act to affect ______. It only affects certain nuclei at a time to see what region is being affected
drug, behaviour
NT specific _____ can be used to identify the role of the NT in a particular behaviour. The toxin is injected directly into the______, which is taken to the ______ and destroys them. Cell bodies that do not use the specific transmitters are ____ affected
neurotoxin nucleus, terminals, not
DA, NE neurotoxin
6-hydroxydopamine (6-OHDA)
5-HT neurotoxin
5.7-dihydroxytryptamine
electrical stimulation that produces action potentials and NT release; can be used to assess whether activation of a nucleus induces certain patterns of behaviour; usually a complementary technique to lesions
implanted microelectrodes
measures NTs released in a specific region while the subject is engaged in behaviour
microdialysis
in microdialysis, artificial _____ is pumped in through a probe implanted at precise sites in brain tissue. _____ enter the solution in the probe via diffusion. Tiny amount of fluid are pumped out of the probe and analyzed by techniques such as ________. The sample rate is _____ minutes.
CSF, NTs, high performance liquid chromatography, 1-2
used with microdialysis to separate the sample into components depending on the molecular size or ionic charge
high performance liquid chromatography (HPLC)
can determine the concentration of molecules of interest
electrochemistry
When a glass tip is placed in front of the membrane and suction is applied to create a small tear so that the membrane wraps around the electrode tip
intracellular patch clamp
intracellular patch clamps allows recording of ______ _____, and changes in ____ ______ (ion flux). it provides detailed information of how drugs affect _______ ________ or ionic currents that regulate neural activity. It is measured in ____/____/_____. To use, the animal must be ____ or an in ____ brain slice preparation must be used
membrane potentials, electrical currents, synaptic transmission, mV, V, Amps, anaesthetized, vitro
When a glass or metal electrode is placed near a neuron and only action potentials are recorded
extracellular microelectrodes
With extracellular recordings, _____ cells can be recorded from at once, and this can be done in ______/_____ animals to assess changes in cell firing associated with behaviour.
multiple, awake, behaving
when a tissue sample is isolated and ground into a homogenate for analysis; often used to quantify the amount of receptors and if there are receptors there
soup methods
uses intact piece/slices of tissue to localize targets in the brain
slice method
ligands embedded in a radioactive atom (e.g. hydrogen) which can be used to index receptor binding by the amount of radioactivity in the sample, or through special photography; not the most selective
radioligands
created by injecting an antigen (e.g. receptor) into a host animal and collecting blood samples. Antibodies are tagged with coloured chemicals or fluorescent dues for visualization; harder to create, not always available
antibodies
proteins that bind to specifically targeted proteins
antibodies
When a solution containing a tissue homogenate or generic cells transfected with specific receptor is incubated with radioligand
radioligand binding
In radioligand binding, cells expressing the receptor of interest are _______ in a solution containing the radioligand. After a _____, unbound radioligand is removed and the remaining amount that is bound to the tissue is measured. It reflects the ______ of receptors in the tissue. You can use this method to identify receptors in a particular brain region by dissecting out that brain region and _______ it
bathed, washout, number, grinding
radioligand binding is also used to identify if a novel drug has some ___/_____ for a particular receptor. Only cells expressing the receptor of interest are used. A standard radioligand is combined with a _____ _____ (not radioligand), and displacement of the standard ligand at different _____ of the test are used as indexes. A wash out is needed to test how much more the test compounds ____ to the receptor. If you need a ____ concentration of test compound to bump off the standard radioligand, it is binding with stronger affinity. You can also test a drug’s affinity for different receptor ________.
affinity/selectivity, test compound, doses, stick, lower, subtypes
_____ assays can be used to look at changes in ______ activity (e.g. concentration of DA on ______ receptor stimulation, and inhibition of ______) by applying different concentrations of a drug to cells to obtain a _____ function, if there is no change in ______ of receptor at different doses of ligand while also sticking to it, it is an _____
agonist, enzymatic, D2, cAMP, dose-response, 2nd messenger, antagonist
To measure enzyme activity in _____ receptors, radioligand bind must be used, while ______ (____) measures can be used for ionotropic receptors, to assess how the drug activates ionic currents mediated by the receptor. Additionally, NTs can be used in conjunction with an ______ to measure electrical change produced by it
metabotropic, electrophysiology, patch clamp, allosteric modulator
When a radioligand is incubated with tissue slices, then exposed to film sensitive to radioactivity; used to visualize receptor distribution and requires highly selective drug
receptor autoradiography
when brain slices are fixed and incubated with an antibody; which attaches to the antigen on cells that contain it; but some antibodies may lose selectivity through adding tags
immunocytochemistry
Receptor autoradiography and immunoctyochemistry work well to tell you ______ in the brain receptors are, but not to _____
where, quantify
In ELISA, proteins in different _____ are placed in a plate containing the substrate. Antibodies are linked to an _____ that acts on a substrate to form a _____ ______. The _____ is proportional to the amount to antigen present. ____ amounts of a target proteins are placed in some wells, while _______ tissue from test samples are placed in others. A computer can then be used to measure the colour to _____ the protein in an unknown sample
concentrations, enzyme, coloured product, intensity, standard, homogenized, quantify
a technique used to locate cells in tissue slices that manufacture a particular protein - detects specific mRNA molecules involved in the synthesis of target proteins
in situ hybridization
In in situ hybridization, single stranded _____ fragments that are _____ to the mRNA of interest are labelled. The amount of mRNA gives an estimate of ____ in cells at a particular time. The advantages is that it is highly ________, easier to ______, can be used when no _____ is available, and is extremely _____. Disadvantages is that just because a cell contains mRNA, doesn’t mean the protein has been made, or inserted into the ____
RNA, complementary, protein, selective, analyze, antibody, sensitive, membrane
uses injected radioactive isotopes to identify areas of brain activity (blood flow, glucose, or O2 utilization) when subject is performing certain task (measure of metabolic energy)
positron emission tomography (PET)
PET has relatively low ______ resolution, as it can take up to 30 minutes for just one sample. The radioactive ligand must also be made and used _______. When combined with radiolabeled drugs that bind to NT receptors, PET can be used to study _______/_____ of those receptors in the living human brain, and _____ NT ______ by measurement of the displacement of the _______. it can also be used to index ___ NT levels. a _____ in radiotracer binding reflects an _____ in NT release. PET only works for ____, ____ and ____, and only works in places where there is high receptor and ___ levels
temporal, immediately, locations/concentrations, endogenous, release, radioligand, basal, decrease, increase, DA, 5-HT, GABA, NT
measures blood oxygenation level dependent (BOLD) signal
functional MRI
fMRI works because _____ and _____ hemoglobin have different magnetic signals. It has a better ____ and _____ resolution than PET, and can be used to measure changes in brain activity when the subject is performing certain ______, or patterns of activity across regions of ______ states
oxygenated, deoxygenated, temporal, spatial, task, resting
analyzes changes in brain function following drug administration, location and time course of drug action
pharmacological MRI
The BOLD signal may not reflect _____ of neurons within a brain region, rather it is reflective of ______ inputs to that region
firing, presynaptic
a measure of synchronous firing in large groups of neurons; readout of how groups of neurons may alter firing near simultaneously (how different parts of the brain are working together)
electroencephalography (EEG)
when characteristic waveforms in large groups of cells can be measured through the scalp due to events such as unexpected stimuli or errors
event related potentials (ERPs)
EEG’s ____ resolution is better than fMRI, but has poorer _____ resolution. It is primarily used to measure _____ activity, with ____ activity being more difficult to distinguish. ERPs can be different in _____ populations, and/or can be altered by ______ drugs. This approach is being used to identify how drugs may _______ brain wave patterns
temporal, spatial, cortical, subcortical, psychiatric, psychoactive, normalize
when the gene for a protein is deleted
knockouts
when the original gene is removed and substituted for another
knockin/transgenes
Issues with genetic alterations, is _____ for the altered gene may mask the effect of the mutation, or that because altered gene function occurs at all stages of development, changes in other brain areas may be responsible for behavioural changes
compensation
selective deletion or expression of gene in only a subset of brain regions
conditional knockout
a newer approach involves _______ of a gene so that it is turned on/off when a specific drug is administered
engineering
used to deliver genetic material into targeted cells of interest
viral vectors
insertion of genes for light sensitive ion channels/pumps into neurons
optogenetics
in optogenetics, genes are inserted via _____ of engineered viral vectors into the brain region of interest. Certain viral constructs can permit greater ______ ______, for example, only expressing proteins in neurons that use a certain NT receptor, or project to a specific brain region. _____ channels expressed in neurons can be activated by light delivered via implanted optic fibers connected to laser or LED
infusions, cellular specificity, opsin
opsin channels are activated when stimulated with a specific _______ of light.
wavelength
excitatory opsin channels
channelrhodopsin
inhibitory opsin channels
halorhodopsin, Arch, NpHR
Optogenetics have great _______ specificity, as they can turn on/off a specific type of neurons for a few seconds
temporal
observed in the living organism
in vivo
measurements performed outside the living body
in vitro
tests closely resembling tests used for humans
face validity
when drug effects in the laboratory closely parallel or predict the clinical effect
predictive validity
extent to which the animal measurement tool actually measures the characteristic being investigated
construct validity
the injection of vehicle solution when the drug agent is absent from the treatment
negative control
drug that produces well-characterized effects on a given behavioural test is tested in addition to the compound of interest; determines that the behavioural test was conducted properly and is appropriately sensitive to the pharmacological manipulation
positive control
the same results recorded each time the test is used
reliability
measures of motor activity
open field test
measures of analgesia
tail flick test, hot plate test, operant analgesia testing
reduction of perceived pain without the loss of consciousness
analgesia
measure of anxiety
light dark crossing task, elevated plus maze, zero maze, novelty suppressed feeding, defensive burying
measures of fear
conditioned emotional response, fear potentiated startle
measures of depressive like behaviour
forced swim test, learned helplessness test, maternal separation, sucrose preference test
the point at which the effort required exceeds the reinforcing value
breakpoint
used to measure impulsivity
stop signal task
Stereotaxically implanted microelectrodes runs small electrical potential; changes in flow of current at electrode tup reflect changes in the concentration of electroactive substance (NTs)
in vivo voltammetry
_____ currents can be used to activate cells, or to record _____ electrical response to many neurons in a specific brain region following drug treatment or other manipulation
macroelectrode, summated
Uses 1000-20,000 distinct complementary DNA sequences on a single chip; Can screen entire genome of an organism in a single experiment on just a few chips
DNA microarrays
Either tracks the metabolic rate for nerve cell firing, or transcription factors for cell activation
autoradiography of dynamic cell processes
Either tracks the metabolic rate for nerve cell firing, or transcription factors for cell activation
autoradiography of dynamic cell processes
increases resolution of an x-ray and provides the image in 2D
computerized tomography (CT)
computerized measurement of distinct waves that different atoms emit when placed in a strong magnetic field and activated by radiofrequency waves; Distinguishes the amount of water that magnetically induces resonance of hydrogen
magnetic resonance imaging (MRI)
Uses MRI-generated data to calculate concentration of brain chemicals and evaluate metabolic changes
magnetic resonance spectroscopy (MRS)
measure diffusion of water through axons and anisotropy (direction of diffusion)
diffusion tensor imaging (DTI)
PET but using commercially available probes; Show changes in blood flow
single-photon emssion computerized tomography (SPECT)
investigates connectivity among brain regions when the individual is awake but not engaged in a task; Can be used to compare connectivity in healthy individuals and individuals with disorders
Resting state fMRI
posterior cingulate cortex, medial PFC, parietal cortex, ventral ACC
default mode network
uses guide RNA to identify a specific genomic sequence to be modified, a section of DNA is cut out, then a new one is introduced
CRISPR
isolating human genes and inserting them into mice to produce animal models of disorders
transgenic mice
Genetically engineered receptor is stereotaxically targeted to specific brain cells then activated or suppressed by administering a ligand created to bind to inserted receptor
chemogenetics
