WITH VERIFIED ANSWERS
Basic functions of Norepi, Dopamine, Serotonin,Acethylcholine and GABA in the CNS -
Answer-1. Excitatory in the CNS
Arousal, reward system, wakefulness, learning, mood, MEMORY, focus, attention
2. Excitatory in the CNS Reward behavior, motor control
3. Excitatory in the CNS, Associated with Mood and is the target for antidepressants
4.Excitatory in the CNS
Arousal, reward, memory, sustains attention.
5.Inhibitory Neurotransmitter in the CNS ( mediates Chloride influx into the cell, making
it hyperpolarized and LESS excitable.GABA regulates CNS excitability, regulates the
N/V center in the CNS, and has muscle relaxation properties
Parkinson's disease - Answer-There is a loss of 80+% of dopaminergic fibers &
dopamine levels in the CNS ( Basal Ganglia).Abnormal movements due to upset of the
BALANCE of dopamine and ACH (not enough dopamine and APPARENT over action of
ACH)
No cure only symptom relief
Carbidopa - Answer-It is a dopa-decarboxylase inhibitor, given with L-dopa, that
diminishes the metabolism of L-DOPA in the GI tract and peripheral tissues increasing
the availability of L-DOPA to the CNS. L- DOPA will cross the BBB
Sinemet - Answer-carbidopa/levodopa
Bromocriptine (Parlodel) - Answer-A straight Dopamine Receptor Agonist ( sounds
good-but not)
Severe side effects OF N/V, Hallucinations, & confusion limit use.
Alzheimer's disease - Answer-reduced synthesis of the neurotransmitter acetylcholine (
ACH ) .
Central Acethylcholinesterase inhibitors - Answer-Donepezil ( Aricept)
Rivastigmine ( Exelon)
Benztropine (Cogentin) - Answer-Blockage of cholinergic transmission produces effects
similar to augmentation of dopaminergic transmission ( because of imbalance)
,Namenda (memantine) - Answer-a NMDA (N-methyl-D-aspartate) glutamate receptor
antagonist
protects brain cells against excess glutamate, a chemical neurotransmitter released in
large amounts by cells damaged by Alzheimer's disease and other neurological
disorders
Attachment of glutamate to cell surface NMDA receptors permits calcium ( with sodium
and potassium) to flow freely into the cell. Over time, this leads to chronic overexposure
to calcium, which can speed up cell damage
Benzodiazepines - Answer-Lorazepam(Ativan)
Alprazolam (xanax)
Diazepam(Valium)
Temazepam(Restoril)
enhance the effect of the central INHIBITORY neurotransmitter gamma-aminobutyric
acid (GABA), enhancing chloride entry into cell, creating in an Inhibitory Post-Synaptic
Potential ( IPSP) , and is used for:
sedative, hypnotic (sleep-inducing) properties
anxiolytic (anti-anxiety) properties
Anticonvulsant properties
muscle relaxant properties
In high doses of many shorter-acting forms, amnesic-dissociative properties are seen.
Z drugs - Answer-Zolpidem ( Ambien)
Not a Benzodiazepine in structure , BUT acts on a specific subset of the
benzodiazepine receptor family..... the BZ1 receptor. ( not a sloppy benzo receptor
agonist)
• In contrast to the benzodiazepines, which non-selectively bind to and activate all BZ
receptor subtypes on the GABA receptor, zolpidem has a higher affinity for the BZ1
receptor subtype on the Benzodiazepine / GABA receptor ( the hypnotic inducing
site..!!!!!)
This selective binding of zolpidem on the BZ1 receptor also explains the relative
absence of muscle relaxant activity, anticonvulsant effects, and minimal tolerance with
prolonged use.
2. Zaleplon ( Sonata) - same mechanism
3. Eszopiclone ( Lunesta) - same mechanism
SSRI MOA and advantages - Answer-SELCTIVELY BLOCK THE REUPTAKE OF
SEROTONIN BACK INTO THE NERVE ENDING, ELEVATING NEUROTRANSMITTER
LEVELS.
ADVANTAGES of SSRI's:
No effect on Dopamine reuptake- no accumulation of Dopamine -low addiction potential
( not addictive )
Little blocking activity at Muscarinic receptor- no anti-muscarinic effects observed-
blurred vision, dry mouth, urinary retention, constipation..etc are observed
Little blocking activity at alpha-adrenergic receptors- no hypotension observed
, Little blocking activity at Histamine H1 receptors - no side effect of sedation
BOTTOM LINE WITH SIDE EFFECTS
•They have far fewer side effects as compared to the original anti-depressants of other
categories of anti-depressants. ( Tri-Cyclic Antidepressants)
•They are safe drugs , even in over dosage.
SSRI DRUGS - Answer-1.Fluoxetine-(Prozac)
2. Paroxetine-(Paxil)
3. Sertraline-(Zoloft)
4. Escitalopram-(Lexapro)
SNRIs and MOA - Answer-inhibits reuptake of NE and serotonin
1. Venlafaxine ( Effexor) 30:1
Ind:--depression, anxiety, pain, bipolar disorder, hot flashes
2. Duloxetine ( Cymbalta)10:1 - affects serotonin to a lesser extent compared to Effexor.
Ind: - depression, anxiety, pain, nerve pain, fibromyalgia
3. Desvenlafaxine ( Pristiq) 10:1 ( 2007 )
Ind: - depression, anxiety, pain, nerve pain, fibromyalgia
4. Levomilnacipran ( Fetzima) 1:2
Ind: - depression, major depression
Atypical Antidepressants - Answer-1. Buproprion- ( Wellbutrin )
-antidepressant and smoking cessation aid
MOA = dopamine, norepinephrine and serotonin reuptake inhibitor
Not much or little effect on serotonin reuptake, and a 2 to 1 effect of norepinephrine
reuptake to dopamine reuptake.
Very little effect on Serotonin reuptake....!!!!!!!
The Antidepressant effect associated with NE reuptake inhibition
Does not cause weight gain or sexual dysfunction as seen with SSRI's
2. Mirtazapine ( Remeron) ( NaSSA)
• a Noradrenergic and Specific Serotonergic Antidepressant (NaSSA)
• Act by antagonizing Central α2-adrenergic receptor and certain serotonin receptors
• By blocking α2-adrenergic auto-receptors , NaSSA's enhances adrenergic and
serotonergic neurotransmission in the brain involved in mood regulation
3.Vortioxetine- ( Brintellix )
-
The exact mechanism of vortioxetine is not fully understood; however, it is thought that
this agent enhances the serotonergic activity in the central nervous system (CNS) by:
Tricylic Antidepressants (TCAs) - Answer-Block NE and Serotonin reuptake back into
pre-synaptic neuron, much like the SNRI drugs. ( but not in the class of SNRI's)
If discovered today, they may have been categorized as SNRI's
Also an alternative- to patients not responding to SSRI's and SNRI's