Lecture 14, Serotonin Flashcards
which blood cells store serotonin?
platelets
targets of serotonin in the free blood
white and brown fat
liver
pancreas
muscles
macrophages
which enzyme converts tryptophan into 5-HTP?
tryptophan hydroxylase
how is 5HTP converted into serotonin?
5-HTP decarboxylase
which form of tryptophan is found in food?
L
serotonin is produced?
directly in the neuron
which transporter transports serotonin into vesicles?
VMAT2
how is serotonin similar to catecholamines?
same vesicular transporter
serotonin storage
25% ready to be released
75% stored
what is the role of SERT
actively reuptakes serotonin into pre synaptic neuron
VMAT2 is inhibited by?
reserpine/ tetrabenzine
which drugs cause reversal of direction of serotonin uptake transporters
PCA and fenfuramine
how does ecstasy affect SERT
binds to SERT and so prevents serotonin
reuptake
phosphorylates SERT to reverse direction
how does ecstasy cause serotonin release from vesicles into cytosol?
inhibition of VMAT2
how does ecstasy cause SERT to pump our serotonin instead of reuptaking it?
SERT phosphorylation
effect of ecstasy on serotonin, adrenergic and dopaminergic receptors
agonists
ecstasy overdose
cardiovascular
neural
musculoskeletal
respiratory
kidney
hyperpyrexia
what is serotonin broken down into?
5-HIAA
how is the final product of serotonin catabolism excreted?
CSF
which mostly enzyme catalyses the breakdown of 5HT
MAO-A
why may MAO-B be present in serotonin nerve terminal
catabolism of other monoamines
rostral group consists of
dorsal raphe and median raphe
caudal group
raphe magnus and raphe pallidus
where does the ventral rostral group send inputs to?
midbrain
diencephalon
basal ganglia
limbic system
cortex
where does the dorsal rostral group send inputs to?
colliculi
the dorsal and ventral rostral group merge to innervate which region?
the forebrain
the spinal cord innervation from which raphe nucleus group?
caudal
serotonin effect on neurons can trigger
depolarisaton or hyperpolarisation
which serotonin receptors are ionic?
5HT3
how many serotonin receptors are metabotropic
14
Gs
4,6,7
Gi
1,1B,1D
Gq
2A,2B,2C
which receptors are found on post/pre synaptic surface?
5HT1 ( inhibitory)
which receptors are mainly on post synaptic terminal
5HT 2,3,4,5,6,7
