Parkinson's disease Flashcards
define idiopathic disease
each case has its own origins
how many % of pop are affected by PD
.5% of pop
what is bradykinesia
slow movements
what is akinesia
no body movements
what is the cause of PD
lack of DOPAMINE in nigra striatum pathway
degeneration of dopaminergic neurons
name some symptoms of PD
paused movements increased rigidity of muscles impaired balance bradykinesia akinesia
what effect does MPTP have on rats
no effect
what is MPP+
neurotoxin that causes permanent symptoms of PD
What does MPP+ do
destroy dopaminergic neurons in nigra substantia pathway
state the process that occurs between MPTP to form MPP+
MPTP - exposed to chemical process with MAO - become neurotoxin MPP+
what does MPTP do
target dopamine producing cells in substantia nigra pathway
what do microelectrode studies show about tonic activity in external pallidus segment
decrease in tonic activity in external pallidus segment
what do microelectrode studies show about tonic activity in internal pallidus segment and thalamus
increase in tonic activity in internal segment and thalamus
what is the function of the motor cortex
plan and initiate voluntary movements
describe processes of basal ganglia at rest
no activity in striatum
globus pallidus is tonically active
inhibition in thalamus
decreased excitement in motor cortex
what is the striatum composed of
caudate and putamen
which features make up the basal ganglia nuclei
striatum and globus pallidus
describe process of basal ganglia during period of excitement
excitement in striatum
inhibited globus pallidus periodically
thalamus would be DISINHIBTED
higher exictement in motor cortex (output)
what effect does an excited striatum have
switch off globus pallidus
what effect does a disinhibted thalamus have
increased excitement in motor cortex
what causes PD symptoms
excessive output from internal globus pallidus - stuck in switched on mode
what surgical options to treat PD
- lesion inhibited output structures
- electrically stimulate basal ganglia
how could cannabis treat symptoms of PD
used as dopamine agonist
which drugs can be used to replace lost dopamine
L dopa - dopamine precursor
apomphone - dopmaine agonist
what is l dopa
dopamine precursor
how to treat globus pallidus to treat PD
allow globus pallidus to be turned off at times
what is deep brain stimulation
device near heart - control chronic movements
how does deep brain stimulation work
allow free body movements to control side effects of PD
what happens if the brain stimulation device is turned off
no free body movements, muscles would seize up
what do schwann cells do
schwann cell sheath promote regeneration
describe effect of PD on basal ganglia
- loss of dopamine output in striatum
- increase activity in internal pallidus segment
- increase inhibition of thalamus and midbrain
- increased motor cortex output
