Class 3 Flashcards
Acetylcholine (ACh, neurotransmitter)
neuromuscular junction, memory
GABA (neurotransmitter)
anxiety
Dopamine (DA, neurotransmitter)
movement, reward
Serotonin (5-HT, neurotransmitter)
mood, sleep
Agonist
drug that mimics or potentiates the action of an endogenous neurotransmitter
Antagonist
drug that blocks or reduces action of an endogenous neurotransmitter
Steps in neurotransmission
- Synthesis and Storage
- Release
- Receptor Binding
- Deactivation
Synthesis and Storage (with example)
1st step in neurotransmission, synthesis from enzymatic actions on precursor molecules, often from diet
ex, l-dopa treating Parkinson’s disease increases function of remaining DA neurons
Release (with example)
action potential reaching terminal opens voltage-gated Ca2+ channels and influx of calcium causes release of synaptic vesicles and dumping of neurotransmitter into synapse
botox prevents calcium from releasing vesibles containing ACh so muscles can’t be activated
Receptor binding
neurotransmitter binding leads to depolarization or hyperpolarization
Protein in postsynaptic membrane
Lock and Key binding of neurotransmitter and receptor
Conformational change in receptor channel
Altered permeability to Na+ (influx=depolarization) or Cl- (influx= hyperpolarization)
Deactivation
turning off neurotransmitter signals
reuptake: recycling of NT into presynaptic terminal (serotonin regulating sleep, eating, and aggression)
Degradation: enzymatic degradation of the NT in the synaptic cleft (acetylcholinesterase)
glutamate
major excitatory neurotransmitter in the brain
endorphins
chemicals that act within the pain pathways and emotion centers of the brain
DRUG EX
Parkinsons’s disease
l-dope increasing levels of DA in remaining DA neurons
Dopamine agonist
DRUG EX
Anxiety
Xanax acting as agonist at GABA receptors to inhibit/hyperpolarize neurons associated with anxiety
benzodiazepines
