Week 3 - Depression Flashcards
Endogenous depression
no apparent cause
Neuropathology of depression
PFC:
Reduced number of glial cells
Reduced neuron size
Reduced volume
Hippocampus:
Reduced number of gaba neurons
Reduced volume
Amygdala:
Overactivation
Monamines in depression
Noradrenaline
Dopamine
Seratonin
Monoamine Oxidase Inhibitor
stops the breakdown of monamines once it has been taken back up
What is the monamine hypothesis for depression
depletion of monamine (noradrenaline, seratonin and dopamine) contributes to the pathology of depression
Noradrenaline brain part in Depression
Locus coruleus
Dopamine brain part
nigrostriatal
mesolimbic
What enzyme can cause depression?
Tryptophan - found in meats, eggs, grains
Creates 5HT
Neurotransmitters in Mania
Increased noradrenaline
Increases in dopamine
Excess seratonin may trigger mania
Mania and Gaba
Gaba neurotransmission is reduced
First generation of anti depressants
Tricylic Antidepressants - block the re-uptake of all monamines
Monoamine Oxidase Inhibitors - block the metabolism of active monamines
Mood elevators
Noradrenaline tri’s
alpha and beta adrenoreceptors
Dopamine tri’s
d1 and d5 receptors
seratonin tri’s
5HT1A receptor
How do Tricyclic anti d’s work
Monamines bind to receptors
Receptors couple to G-proteins
Second messenger system is activated
postsynaptic potentials are activates
monamines leave receptor binding sites/g proteins uncouple
monamines are transported back to presynaptic terminal re-uptake
Monoamines are broken down or re-packaged
2nd generation ant depressants
Focus on the re-uptake of serotonin or noradrenaline or both
SSRI’s - seratonin
NRI’s - noradrenaline
SNRIS’s - Seratonin and noradrenaline
how does ketamine work for depression
NMDA gaba agonist
how does psilocybin work
5HT2A receptor agonist
Mania in depression
Increased noradrenaline, seratonin and dopamine
Decreased gaba
- treatments need to decrease overall neurotransmission
Treatments for mania
Mood stabilisers
Lithium carbonate salts
Anticonvulsants
Neuroleptics
How do lithium salts work?
stabilise neurons by reducing the ability of receptors to communicate with second messenger systems
EPSP not produced
How do anticonvulsants work
Prevent positive ion channels from working - also inhibit second messenger systems
