neurotransmitters Flashcards
ionotropic NTs bind to what type of receptors?
ligand-gated channels
metabotropic NTs bind to what type of receptors?
G-protein coupled receptors
ligands
chemicals that bind to receptors
endogenous ligands
neurotransmitters
exogenous ligands
psychoactive drugs
agonist
initiates normal effects on receptors
inverse agonist
initiates NT effects opposite of normal function
antagonist
blocks receptor from being activated
major classes of NTs
acetylcholine, monoamines, amino acids, neuropeptides, soluble gases
acetylcholine CNS functions
attention, learning, memory
alzheimer’s disease associated with (high or low) (what NT)
low ACh
acetylcholine PNS functions
muscle movement, some autonomic NS
acetylcholine receptors
nicotinic and muscarinic
nicotinic receptors: what type of channel?
l-g Na+ channel (EPSP)
nicotinic receptors: agonist
nicotine
nicotinic receptors: effect what muscle?
skeletal muscle
curare
antagonizes skeletal muscle
muscarinic receptors: ionotropic or metabotropic
metabotropic (IPSP)
muscarinic receptors: what NS response
parasympathetic response
monoamines
modified from a single amino acid
monoamines subdivisions
catecholamines and indolamines
catecholamines subdivisions
dopamine, epinephrin and norepinephrine
dopamine pathways
mesolimbocortical and mesostriatal
mesolimbocortical pathway
reward center
mesostriatal pathway
movement
dopamine functions
movement, attention, motivation, learning, reinforcement
dopamine receptors
all metabotropic
dopamine related illnesses
parkinson’s, schizophrenia, autism, ADHD
epinephrine
adrenalin
epinephrine and norepinephrine: CNS functions
arousal and vigilance
epinephrine and norepinephrine: PNS functions
sympathetic function, epinephrine released as adrenalin
epinephrine and norepinephrine: receptors
adrenoreceptors, all metabotropic
indolamines subdivision
serotonin
serotonin: functions
mood, social behavior, appetite, sleep
serotonin: receptors
19 receptors, all metabotropic except 5-HT3
serotonin: effects of antidepressants
antidepressants drugs block 5-HT reuptake to increase activity in cleft
SSRIs
selective serotonin reuptake inhibitors
serotonin: hypothesis of depression
caused by low levels of monoamines, especially 5-HT
serotonin: neuroplasticity hypothesis of depression
chronic stress and depression cause neuroplastic changes in limbic system
serotonin: neuroplasticity hypothesis of depression (SSRIs)
increase 5-HT and brain derive neurotrophic factor
brain derived neurotrophic factor
protein that promotes neuroplasticity and neurogenesis
amino acids subdivisions
glutamate, GABA, glycine
glutamate: excitatory or inhibitory
excitatory
glutamate: receptors
AMPA, Kainate, NMDA
AMPA
Na+ channel
Kainate
Na+ and K+ channel
NMDA
Ca++ channel, longer lasting effects
glutamate: excitotoxicity
neural injury (stroke) causes an excess release of glutamate, which is toxic to neurons
GABA: excitatory or inhibitory
inhibitory
GABA: receptors
GABA(A) and GABA(B)
GABA(A) receptor
ionotropic, fast
GABA(B) receptor
metabotropic, slow
GABA: target for what medications
anti-anxiety and tranquilizers
tranquilizers
anxiety, epilepsy, insomnia, pain
GABA: related illness
schizophrenia, decreased GABA in prefrontal cortex
glycine: excitatory or inhibitory
inhibitory
glycine: location
spinal cord and brainstem
neuropeptides subdivisions
endorphins
neuropeptides: co-released with other NTs (effects)
modulates effects of other NTs, released at all parts of the axon terminal, enzymes destroy NP after release
endorphins
endogenous opioid peptides
endorphins: related functions
analgesia (pain relief), reward
soluble gases subdivision
nitric oxide
nitric oxide: location
produced in dendrites, diffuses as soon as it is produced
nitric oxide: retrograde transmitter
diffuses backwards from postsynaptic to presynaptic neuron
retrograde transmitter effects
activates second messenger pathways, modulates other NTs
nitric oxide: process
- activates NMDA receptors (Ca++)
- protein cascades (postsynaptic neuron)
- produces nitric oxide
- releases more glutamate than normal (presynaptic neuron)