MSN 671 Final Exam Focus Points
Classic synaptic neurotransmission - answer· An electrical current travels down the
presynaptic neuron, releasing neurotransmitters and sending these chemical
messengers to the postsynaptic neuron's receptors. The receiving neuron then converts
the chemical message back into an electrical impulse or results in a cascade of
sequential chemical messages
Ligand-gated ion channel - answerA receptor and a channel
Ligand: a NT, drug, or hormone that binds to a receptor
Can immediately alter the flow of ions when ligand binds
-Ligands can fall anywhere along the agonist spectrum to alter ion flow
Ligand - answerLigand: a NT, drug, or hormone that binds to a receptor
Ligand-gated ion channel subtypes - answerPentameric (5 protein subunits): GABA-A,
Nicotinic receptors, Strychnine-sensitive glycine receptors, 5HT3 receptors
Tetrameric (4 protein subunits): AMPA, Kainate, NMDA
Voltage-sensitive ion channel - answerOpening and closing altered by ionic charge or
voltage potential
Two types: Sodium and Calcium
Sodium-charged ion channel - answerEssential for action potentials
Made of 4 subunits forming a central alpha pore; each subunit is made of 6
transmembrane segments:
-Segment 4= voltmeter
-Segment 5-6= ionic filter (only allows Na through)
-Between 3rd and 4th subunits= amino acid plug/pore inactivator
Site of action of many anticonvulsants
Presynaptic transporter - answerCollects NTs from the synapse and transports them
back into the neuron for packaging and release
Monoamine: SERT, DAT, NET
GABA: GAT
, Glutamate: EAAT
Norepinephrine role - answerhelps control alertness and arousal, stress response,
cognitive functioning, attention/focus
Linked to fight or flight
Acetylcholine role - answerMotivation, memory, cognitive functioning, sleep
Melatonin role - answerSleep
Released from the pineal gland (increased in darkness)
Serotonin role - answerSleep, mood, sexuality, appetite, pain
Dopamine role - answerReward/pleasure, executive functioning, wakefulness, learning,
motor control
GABA role - answerInhibitory
Sleep, mood regulation
Histamine role - answerinflammation, alertness/wakefulness
Process of melatonin production - answer-During darkness, there is no input from the
retinohypothalamic tract to the suprachiasmatic nucleus (SCN) in the hypothalamus--
>Signals the pineal gland to produce melatonin
-MT1 receptor then inhibits neurons in the suprachiasmatic nucleus , decreasing the
wake-promoting actions there
Process causing tardive dyskinesia with an antipsychotic - answer· Chronic blockade of
D2 receptors in the nigrostriatal pathway (D2 receptors are normally inhibitory of the
"STOP" pathway, making it "GO"--> acute blockade causes "STOP" to predominate,
resulting in slow and rigid Parkinsonism-like movements)
-->Receptors then upregulate, causing supersensitivity of receptors and the opposite
situation (not enough "STOP") and, therefore, the rapid, hyperkinetic, involuntary
movements of TD)
· Late and delayed in onset (months to years of treatment)
· Can be irreversible
How can antipsychotics cause breast discharge - answer· By blocking the
tuberoinfundibular pathway (projects from hypothalamus to pituitary gland), which is
normally tonically active and inhibits prolactin release
· This blockade causes a rise in prolactin--> galactorrhea
Classic synaptic neurotransmission - answer· An electrical current travels down the
presynaptic neuron, releasing neurotransmitters and sending these chemical
messengers to the postsynaptic neuron's receptors. The receiving neuron then converts
the chemical message back into an electrical impulse or results in a cascade of
sequential chemical messages
Ligand-gated ion channel - answerA receptor and a channel
Ligand: a NT, drug, or hormone that binds to a receptor
Can immediately alter the flow of ions when ligand binds
-Ligands can fall anywhere along the agonist spectrum to alter ion flow
Ligand - answerLigand: a NT, drug, or hormone that binds to a receptor
Ligand-gated ion channel subtypes - answerPentameric (5 protein subunits): GABA-A,
Nicotinic receptors, Strychnine-sensitive glycine receptors, 5HT3 receptors
Tetrameric (4 protein subunits): AMPA, Kainate, NMDA
Voltage-sensitive ion channel - answerOpening and closing altered by ionic charge or
voltage potential
Two types: Sodium and Calcium
Sodium-charged ion channel - answerEssential for action potentials
Made of 4 subunits forming a central alpha pore; each subunit is made of 6
transmembrane segments:
-Segment 4= voltmeter
-Segment 5-6= ionic filter (only allows Na through)
-Between 3rd and 4th subunits= amino acid plug/pore inactivator
Site of action of many anticonvulsants
Presynaptic transporter - answerCollects NTs from the synapse and transports them
back into the neuron for packaging and release
Monoamine: SERT, DAT, NET
GABA: GAT
, Glutamate: EAAT
Norepinephrine role - answerhelps control alertness and arousal, stress response,
cognitive functioning, attention/focus
Linked to fight or flight
Acetylcholine role - answerMotivation, memory, cognitive functioning, sleep
Melatonin role - answerSleep
Released from the pineal gland (increased in darkness)
Serotonin role - answerSleep, mood, sexuality, appetite, pain
Dopamine role - answerReward/pleasure, executive functioning, wakefulness, learning,
motor control
GABA role - answerInhibitory
Sleep, mood regulation
Histamine role - answerinflammation, alertness/wakefulness
Process of melatonin production - answer-During darkness, there is no input from the
retinohypothalamic tract to the suprachiasmatic nucleus (SCN) in the hypothalamus--
>Signals the pineal gland to produce melatonin
-MT1 receptor then inhibits neurons in the suprachiasmatic nucleus , decreasing the
wake-promoting actions there
Process causing tardive dyskinesia with an antipsychotic - answer· Chronic blockade of
D2 receptors in the nigrostriatal pathway (D2 receptors are normally inhibitory of the
"STOP" pathway, making it "GO"--> acute blockade causes "STOP" to predominate,
resulting in slow and rigid Parkinsonism-like movements)
-->Receptors then upregulate, causing supersensitivity of receptors and the opposite
situation (not enough "STOP") and, therefore, the rapid, hyperkinetic, involuntary
movements of TD)
· Late and delayed in onset (months to years of treatment)
· Can be irreversible
How can antipsychotics cause breast discharge - answer· By blocking the
tuberoinfundibular pathway (projects from hypothalamus to pituitary gland), which is
normally tonically active and inhibits prolactin release
· This blockade causes a rise in prolactin--> galactorrhea
