Chemical Msngr & Excitotoxicity Karius T#2 Flashcards
Where are serotonergic nerurons found?
Raphe nuclei
What are the five monoamines?
- epinephrine
- norepinephrine
- dopamine
- serotonoin
- histamine
Where is Norepinephrine found, what is its role, & how is it made?
- Locus ceruleus, other pontine and medullary areas
- Plays a role in wakefulness and alertness
- Derived from Tyrosine- moved into vesicles where it is made
Where is epinephrine found, what is its role, & how is it made?
- Found in medulla
- Modulatory role
- Derived from tyrosine which makes dopamine, then NE, from here Epi is made.
- NE is made in vesicles and neurons have PNMT that convert NE to epi after it leaves the vesicles.
- Epi is then moved back into the vesicles
How is epi and NE moved into vesicles and what drug targets this?
- VMAT1 and VMAT2
- Reserpine inhibits this leading to synaptic failure
How is th action of epi and NE limited?
- Reuptake where they are degraded with MAO
- Enzyme degradation with MAO
- COMT also degrades
What do NE and Epi bind to?
- alpha adrenergic
beta adrenergic
Where do you find dopamine, how is it made, how is it limited, what are its receptors?
- Basal ganglia for motor control and hypothalamus & limbic system for endocrine and emotional control. Also cortex
- Made from tyrosine using tyrosine hydroxylase (RLS)
- Reuptake and catabolism by MAO and COMT
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What are dopamines receptors?
- Metabotropic (Serpentine) receptors
- GPCR’s
- D1 and D5 increase cAMP using Gs
- D2 decrease cAMP and increase potassiium efflux
- D3 and D4 decrease cAMP using Gi
Where do you find 5HT, what is it, how is it made, how is it limited?
- Brainstem Raphe nuclei for modification of motor and sensory actiity. Hypothalamus and limbic system for mood and cerebellum for mods of motor activities.
- Serotonin
- Derived from trp using trp hydroxylase
- Reuptake and catabolism by MAO and COMT
What are serotonin’s receptors?
- 7 receptors with mutliple subtypes
- Serepentine receptors
- One Ionotropic receptor 5HT3 for sodium influx
- 5HT3 is in area postrema for vomiting
- 5HT6 has an anti-depressant effect
Where do you find histamine, what is its role, how is it made, how is it limited?
- Tuberomammillary nucleus of hypothalamus
- Wakefulness
- Derived from histidine using his decarboxylase
- limited with reuptake and DAO and COMT
What are histamines receptors?
- Serpentine receptors
- H1: PLC activation
- H2: increase campt
- H3: presynaptic decrease histamine release
- H1 involved with wakefulness
- More H1 and H3 in the brain than H2
What are the two major inhibitory amino acids?
- GABA
- Glycine
Where is GABA found?
- Cortex
- cerebellum
- basal ganglia
- amounts start very small at spinal cord and increase as you move superior