18 Flashcards
a single neuron in the CNS might receive input from 100’s of axons
whether AP’s are propagated or not depends on _ _ _
number and types of POSTsynapic receptors
synchrony on incoming signals
frequency of incoming signals
NT’s (really neuromodulators) that act on _ receptors will ultimately modify the activity of synaptic proteins.
these can be located pre or postsynaptically
G protein coupled receptors
pre or post
Dopamine - Gprotein
Dopamine receptors - Gprotein can either be Gs or Gi but they all either increase or decrease _
D1 and D5 - increase cAMP
D2,3,4 - decrease cAMP
D2 are receptors linked to Galphai - decrease cAMP- antagonists of these are important
Serotonin Receptors are most _ receptors
G protein - are increasing or decreasing cAMP
5-HT3 - ligand-gated Na and K cation channel - depolarizing plasma membrane - excitatory
Glutamate acts as an excitatory NT(opens Na channels) and sometimes it acts as a neuromodulator (activates a Gprotein coupled receptor)
what does ionotropic vs metabotropic mean
ionotropic - letting Na in - all excitatory
metabrotropic - Gprotein
GABA receptors activate Cl- channels and produce hyperpolarization
what binds here
barbs
benzodiapiens
ethanol
GABA binds to its receptor - opioids block the binding - causing excitation - inhib the inhibitor
_ receptors activate Cl- channels and produce hyperpolarization
THC receptors interact with and potentiate the activity of these receptors
glycine receptors
strychnine poison - antagonist of glycine receptor - causeing inhib of the inhibitor - more excitable
“positive” symptoms of schizophrenia linked to excess _
delusions, aduitory hallucinations, distrubances in though
excess dopamine
mesolimbic pathway
“negative” symptoms of schizophrenia - linked to _ pathologies
loss of affect, catatonia, immobility
prefrontal pathologies
mesocortical pathway
NC- negative mesoCORTIcal
hypofxn of _ receptors as a primary or big player in pathophysiology of schizophrenia
- Clozapine on negative symptoms and cognition may be thru activation of the GLYCINE modulatory site on the _ receptor
NMDA
glycine modifies NMDA
this is the Glutamate hypothesis
past present and future thinking about anti-psychotic drugs (APD) and schizophrenia
past - excess Da activity - D2 anatagonists - currently how it is treated
present - renewed interest in the serotonin - combined 2 and D2 antagonists
future - cortical-midbrain imbalance - multiple NTs
clinical effects of anti-psychotics
_ effects - parkinson’s like symptoms, akathsia- forward tilt of trunk, rigidity,
extrapyramidal effects
why atypical antiphsyotics are popular
anatagonism of D2 and D4 DA,, serotonin, Histamin, al adrenergic, muscarininic M1 all involved with producing the therapeutic and adverse effects of anti-pyschotics they are all _ receptors
all Gprotein coupled
classical typical vs newer atypical antipsychotics
receptors?
extrapyramidal side effects?
positive/negative symptoms tx
classical - D2 block, extrapyramidal side effects, hyperprolactinemia, effective against positive symptoms
atypical - 5HT2, D4, weak D2, lesser EPS and hyperprotinemia - due to weak D2 effect
effective against postive and negative symptoims
depression was due to a defincieny of _ NT’s notably norepinephrine and serotonin
monoamine NT’s
NE and 5HT
