Flashcards in CNS Pharmacology Deck (45):
Major function of CNS
Processing info and generating the appropriate response
Name the excitatory CNS Neurotransmitters
Glutamate (Most abundant)
Name the inhibitory CNS neurotransmitters
Drug classes causing CNS depression (incr inhibition, decr excitation)
(From lowest effect to greatest)
Drug classes causing CNS stimulation (incr excitation, decr inhibition)
(From lowest effect to greatest)
The balance between excitation and inhibition in the brain can mean life or death? True or False
What is the process of CNS excitability by Glutamate?
When GLU activates the NMDA receptor > influx of Ca + Na > excitation
What is the mechanism of GABA inhibitory effect on neurons?
When you activate GABA a receptor > influx of Cl > decr ability of cell to respond/dampens cell's activity
What is going on neurologically with a seizure?
Excessive and abnormal brain cell activity arising from too much excitation or too little inhibition
What is the mechanism of action of anti-convulsants?
Acts to limit the initiation or spread of a seizure by working to enhance GABA > reduces excitability of the neurons
Acts as anticonvulsant at doses below those that produce anesthesia
What are the general effects of tranquilizers-sedatives?
They often work synonymously to decrease anxiety and produce a mild sense of drowsiness; calming effect or chemical restraint
What are the classes of tranquilizers-sedatives?
Phenothiazine, butyrophenone, and benzodiazepines (GABA)
What are hypnotic sedatives?
Agents that produce calm (sedative) and sleep (hypnosis); dose-dependent spectrum of sleep, CNS depression, and sedation ; NOT anesthesia
Uses of Narcotics
Induces deep sleep; drug class = morphine
- patients cannot be easily aroused from sleep
What does it mean that the effects of CNS depressants can be additive or synergistic?
This may cause global depression of critical CNS functions (e.g. Alertness, breathing, CV control) and lead to unexpected coma and/or death
Fight or flight NT
Function of Norepinephrine
What NTs are classified as monoamines (biogenetic amines)?
What NTs are classified as amino acids & derivatives?
What NTs are classified as neuropeptides?
What are monoamines?
Substances that act as peripheral transmitters as well as those that act almost entirely within the CNS (dopamine)
- synthesis, release, and elimination mechanisms in CNS are identical to peripheral neurons
-DO NOT CROSS BBB
-broken down by MOA
What is the biosynthetic precursor of dopamine, EPI, and NE? Elimination method?
L-tyrosine; uptake or MAO
What is the biosynthetic precursor of Histamine? Elimination method?
What is the biosynthetic precursor of Serotonin? Elimination method?
L-tryptophan; uptake or MAO
-generally considered to be excitatory transmitters (esp. NE and DA) for most brain functions
- drugs may activate or block receptors
What is an example of a catecholamine used therapeutically?
Imipramine- inhibitor of CA + uptake (NE, EP, DA)
- used for narcolepsy, cataplexy (stimulates arousal)
What is an example of a monoamine oxidase inhibitor?
Selegiline - used to treat canine cognitive dysfunction
What are the effects of acetylcholine antagonists on CNS?
CNS depression, delirium, short-term memory loss
Define serotonin (5-HT)
- synthesized from L-tryptophan
-eliminated similar to CA > degraded by MAO and uptake by 5-HT transporters
-many 5-HT receptors
- effects: regulation of mood, appetite, sleep/wake cycles, sensory perception
Examples of serotonin therapeutic agent
Used for OCD, aggression
-clomipramine: NERI & SSRI
-used for separation anxiety
What are the effects of serotonin syndrome?
High body temp, tachycardia, diarrhea, and agitation
What are the CNS effects of GABA agonists?
GABA antagonists cause what CNS effects?
Examples of GABA Therapeutic agents
-Barbiturates: GABA agonists
Uses: sedation, euthanasia
-Benzodiazepines: GABA agonist
Uses; anxiety, sedation
Other examples of Catecholamine Therapeutic agents:
Acepromazine: DA antagonist
- Reserpine: destroys CA vesicles
Uses: sedative (works well in horses)
-Xylazine: alpha2 agonist
Drugs that block excitatory amino acids (EAAs) have what effects?
Decreased excitation or inhibition
Example of an EAA Therapeutic Agent
Ketamine: NMDA receptor