LS6027 TB1 Flashcards
what is the function of a neuron
transmit and process infomation
Central Nervous System
(CNS) consists of?
Peripheral Nervous
System (PNS) conisists of?
CNS: Brain and spinal cord
PNS: Somatic nervous system
(spinal nerves, cranial
nerves), Autonomic nervous system
What functions are the CNS and the PNS responsible for
CNS:
* Integrates and co-ordinates
sensory data and motor
functions
* Higher functions including
intelligence, memory and
emotion
PNS:
* Allows communication
between CNS and rest of
body
* Afferent division (sensory)
* Efferent division (motor)
what are the functuions of these important structures in the brain
* Cerebral cortex (neocortex)
* Thalamus
* Hypothalamus
* Basal ganglia
* Limbic system
- Cerebral cortex (neocortex) – a variety of complex
functions. From forebrain - Thalamus - ‘relay station of the brain’. In forebrain. Most
sensory inputs are received here - Hypothalamus - controls autonomic and endocrine
systems; survival behaviour and homeostasis. In forebrain - Basal ganglia - collection of nuclei in midbrain; roles in
movement and reward - Limbic system - emotion, some instinctive behaviour,
reward/punishment. Mostly in forebrain
what are the functions of these other crtical cels in the brain?
Astrocyte
Blood vessel
Microglia
Oligodendrocyte precursor cell (OPC)
Oligodendrocyte
Astrocyte: modulates synapses
Blood vessel:delicers O2 + glucose
Microglia: Inflammatory cell
OPC: ‘stem cell’
Oligodendrocyte: produces myelin
list the differences between ionotropic receptors(3) and metabotropic receptors(4)
Ionotropic receptors
– Ligand-gated ion channels
– one or several binding sites for neurotransmitters
– rapid, transient responses
Metabotropic receptors
– transmembrane proteins
– usually act on internally gated ion channels
– slower but more prolonged responses
– responses can be very complex
what are the 3 agonisitic effects agonists can have on neurotransmitter action
mimic, prolong or enhance neurotransmittrer action
what are 5 mechanisms of action of agonists on neurotransmitter action
– Precursor for neurotransmitter e.g. L-DOPA
– Stimulate transmitter release
– Block autoreceptors - stimulate synthesis/release
– Stimulate postsynaptic receptor
– Block reuptake or breakdown of transmitter
what are the 3 antagonisitic effects antagonists can have on neurotransmitter action
– Inhibit neurotransmitter synthesis
– Prevent packaging in synaptic vesicles
– Bind + stimulate autoreceptors, inhibiting synthesis/release
– Inhibit transmitter release
– Bind and block postsynaptic receptors
what are the 7 approaches to studying the human brain
Postmortem studies
Scanning: MRI/CT/PET
Electroencephalogram (EEG)
Transcranial Magnetic Stimulation (TMS)
Biochemistry of CSF/blood/urine
Platelets
Neuroendocrine
What are the 7 techniques used for postmortem studies
- Gross anatomy
- Radioligand receptor binding
- Autoradiography
- Immunocytochemistry
- Radioimmunoassay
- In situ hybridisation
- DNA microarrays
what are the 5 main issues associated with studying PM brain tissue
1) stability
2)Indentification
3)Cause of death
4)Established time of death
5)Drug treatment prior to death
What are the 3 advantages associated with studying PM brain tissue
1)direct study of the brain
2)allows abnormalities to be linked to particular regions
3)long term studies - keep brain frozen
what is Bmax?
maximum binding density of receptors (receptor number)
what is Kd?
affinity constant for ligands binding to receptor
what does radioligandreceptor binding assays use when studyig the human brains?
homogenates of brain tissue
what does autoradiography allow when studying the human brain
allows visualisation of receptor distribution in the brain
what does immunocytochemistry involve when studying the human brain
involves raising antibodies to receptors/enzymes/neurotransmitters etc
how does magnetic resonance imaging (MRI) work for study of the human brain?
subject is xposed to strong magnetic field and activated by radiofrequency waves
what does fMRI stand for?
and what does it do?
functional magnetic resonance imaging
measures blood flow to brain regions
what are PET scans
what are the 3 main uses
positron emisssion tomography
1)lovalising specfic nerve endings that contain specific NTs
2)Dectecting NT receptors
3)using 18F deoxyglucose (FDG) taken up by actively respiring tissues but not metabolised
what does EEG stand for?
and what is it
Electroencephalogram
Hat with recording electrodes allowing, picks up various types of electrical activity in the brain
non-invasive
what does TMS stand for?
transcraial magnetic stimulation
What is CSF
Cerebro spinal fluid
