Neurochemistry Flashcards
Carrot shaped eosinophilic inclusions seen on hematoxylin and eosinophilic stains
Rosenthal fibres
What are Rosenthal fibres the diagnostic signature of?
Alexander’s leukodystrophy
What are Hirano bodies?
Oval to enlongated rod-shaped, eosinophilic inclusions
When would you find high numbers of Hirano bodies?
Alzheimer’s
What type of receptors are beta-adrenergic?
Gs coupled - increase adenylate cyclase
What type of receptors are Alpha 1 receptors?
Phospholipase C coupled
What type of receptors are alpha 2 receptors?
Gi-coupled (inhibitory)
What is the precursor of serotonin?
Tryptophan
What does tryptophan become before serotonin?
5hydroxy 1-tryptophan
What type of receptor is GABA-A?
Ionotropic
Which cells produced GABA in the cerebellum?
Purkinje
What does the loss of GABA neurones in the caudate and putamen occur in?
Huntington’s
What is the predominant CNS metabolite of NA?
MHPG
Outside of the brain, what is the predominant metabolite of NA?
VMA (this is why levels of VMA increase in peripheral NA producing tumours such as phaeochromocytoma)
Can NA cross the BBB?
No
Can NA metabolites cross the BBB?
No other than MHPG
Name 2 inhibitory amino acids
GABA
Glycine
What type of receptor is a D2 receptor?
Presynaptic inhibitory receptor - dopamine inhibits its own release through D2 autoreceptors
2 examples of catecholamines
Dopamine and Noradrenaline
Example of an indolamine
Serotonin
Which enzyme is involved in GABA metabolism?
GABA transaminase
Which are the D1-like receptors?
D1 and D5
Which are D2-like receptors?
D2, D3, D4
Effect of D1-like receptors on cyclic AMP
Increase
Effect of D2 like receptors on cyclix AMP
Decrease
Where would you find D1 and D2 receptors?
Caudate and putamen
Where would you find D3 receptors?
Nucleus accumbens
Where would you find D4 receptors?
Prefrontal cortex
Where would you find D5 receptors?
Hippocampus
What is the rate limiting step is biosynthesis of dopamine?
Tyrosine hydroxylase
MOA of ketamine
Non-competitive antagonist at NMDA receptors
Which receptors mediates long-term potentiation?
NMDA
Where do glycine and d-serine act as co-agonists at?
NMDA receptors
What type of receptor is a glucocorticoid receptor?
Ligand dependent regulator of nuclear transcription
What is released when nicotine binds to receptors?
Dopamine
What breaks down dopamine?
COMT
MAO
What is MAO-A more selective of?
Noradrenaline and Serotonin
What is MAO-B more selective of?
Dopamine
What does LSD cause stimulation of?
5HT-2
Which receptors may be downregulated after ECT/antidepressant treatment?
5HT-2
What does 5HT-7 regulate?
Circadian rhythm
5HT1a agonist action
Antidepressant
5HT1B action
Aggression
5HT1D antagonism action
Antimigraine
5HT2a antagonist action
Antipsychotic
5HT2A agonism
Hallucinogenic
5HT2B stimulation
Cardiac valvular fibrosis
5HT2C agonist
Anorexic effect
What type of receptor is a GABA-B receptor?
G-protein coupled
What is a selective agonist of GABA-B?
Baclofen
Synthetic enzyme of glutamate
Glutaminase