topic 5 (neurotransmitters in health and disease) Flashcards
what receptors are invovled in long term potentiation
glutamate receptors
how does glutamate cause excitotoxicity
- follwing injury or death to a glutamatergic neuron glutamate is released
- this can excite the neighbouring cells and be neurotoxic
what is autoimmune encephalitis
- antibodies are produced by the body against different receptors in the brain
- this causes a variety of conditions some can be fatal
what are 5 modulatory pathway neurotransmitters
dopamine, acetylcholine, serotonin, noradrenaline
what is the function and disease of the nigrostriatal dopamine pathway
modulation of movement
parkinsons disease
what is the mesolimbic/mesocortical dopamine pathway involved in
behaviour
schizophrenia, addiction
what is the tuberohypophyseal system involved in
prolactin
between the hypothalamus and the pituitary gland
why does the substantia nigra lose pigmentation in parkinsons disease
- melanin is a breakdown product of dopamine
- as neurons in the Substantia nigra lose dopamine the area loses pigmentation
what are 5 key parts of the basal ganglia
striatum thalamus globus pallidus subthalamic nucleus (stn) substantia nigra
outline the direct pathway
- excitatory
- motor cortex excities striatum with glutamate
- Striatum inhibits the globus pallidus with GABA
- because the globus paladus normally inhibits the thalamus with GABA, inhibition on the inhibition causes the thalamus to be excited
- The thalamus excites the motor cortex leading to more movement
outline the indirect pathway
-inhibitatory
- motor cortex excites striatum with glutamate
- The striatum inhibits GPe with GABA.
- GPe normally inhibits the STN with GABA, so inhibition of this inhibition causes an increased STN activity.
- The STN excites the GPi with glutamate
- The GPi inhibits the thalamus, so increased activity of the GPi causes less thalamus activity
- The thalamus normally excites the motor cortex so inhibition of the thalamus causes less movement
outline the nucleus basalis cholinergic pathway
- projection from the nuclei in the basal forebrain to the cortex
- function in memory and arousal
- degeneration in alzheimers disease
outline the serotinergic pathways from the raphe nuclei
- projects across the cns including the cortex, hippocampus and limbic system
- multiple different receptors
- involved in mood, sleep, appetite, pain regulation
- involved in depression, anxiety and chronic pain
- drugs include SSRI’s and tricyclic antidepressantsq
outline the noradrenergic pathway from the locus correlus
- widespread projection across the CNS
- involved in arousal, mood and blood pressure control
- drugs include amphetamines and methyl dopa
what is the uk brain bank criteria for parkinsons diagnosis?
Bradykinasia AND 1 of tremor rigidity postural instability