basal ganglia Flashcards
exam 1
striatum receives input from
cortex
blood supply to striatum
br. of ACA and MCA
main out put to the thalamus
globus pallidus
blood supply of the globus pallidus
anterior choroidal artery, lateral striate arteries and MCA
what is a key component of the indirect pathway?
subthalamic nucleus
blood supply to subthalamic nucleus
branches of PCA and PCOM
pars compacta
produces dopamine
pars reticulata
output to thalamus
blood supply to substantia nigra
br. of PCA and PCOM
key inhibitor/activator of striatal activity
substantia nigra
what is the most medial structure of the basal ganglia
Globus pallidus
tell me about the vessels of the basal gnaglia
very vulnerable for hemorrhage
what type of motor system is the basal ganglia?
extrapyramidal
dopamine activates the direct pathway via
D1 receptors
dopamine in the direct pathway leads to a
stronger net activation
facilitaates voluntary movement “stepping on the gas”
direct pathway
dopamine inhibits the indirect pathway via
D2 receptors
inhibits involuntary movements “hitting the brakes”
indirect pathway
bradykinesia, resting tremor, rigidity, postural instability
parkinson
is there a slightly more male prevalence in parkinson’s dx.?
yas
what happens to the direct pathway in parkinson?
there is a decreased net activation due to the low dopamine
lewys bodies are found
substantia nigra, olfactory bulb and anywhere in the CNS
what are some of the treatments for parkinson
medications: like L-dopa or medications that either act like dopamine (agonists) or prolong dopamine activity
surgery- lesioning or deep brain stimulation. targets are STN and GP
huntigton’s caused by a
CAG repeats
pathology of huntigton’s
neuronal loss and gliosis in striatum leading to atrophy and chorea
what inhibits the indirect pathway?
dopamine
oscillatory movements
tremor
violent, flailing movements
hemiballismus
rapid, jerky movements
myoclonus
involuntary contractions
dystonia
semivoluntary, stereotyped movements
tics
