Module 14A CNS Flashcards
1
Q
Neuropharmacology
A
- Study of drug effects on CNS function
- Treatment of biochemical imbalance
2
Q
Neuron Function
A
- Excitable cells
- Transmit through electrical/chemical signals
- Starting at dendrite
- Cause action potentials
- Pre-synaptic terminal release neurotransmitters
3
Q
Action Potential
A
- Neuron to neuron communication
- Resting potential -70mV
- Na+ enter cell during depolarization
- K+ channels open after Na+ close
- K+ leave cell during repolarization
4
Q
Synapse
A
- AP reaches pre-synaptic terminal
- Influx of Ca++
- Neurotransmitter vesicles fuse with membrane
- Neurotransmitters release onto synaptic cleft
- Bind to receptors on post-synaptic membrane
5
Q
CNS Neurotransmitters
A
- Chemicals transmit signals across synapse
- Broken into classes
6
Q
Monoamine Classes
A
- Norepinephrine (depression/anxiety)
- Epinephrine (anxiety)
- Dopamine (parkinson/schizophrenia)
- Serotonin (depression/anxiety)
7
Q
Amino Acid Classes
A
- Excitatory, glutamate/aspartate (alzheimers)
- Inhibitory, GABA/glycine (anxiety)
8
Q
Other Class
A
- Acetylcholine (alzheimer/parkinson)
9
Q
Replacement
A
- Drug replaces neurotransmitters
- Low in diseases
10
Q
Agonist/Antagonist
A
- Drug binds to receptors
- Post-synaptic membrane
11
Q
Neurotransmitter Breakdown Inhibition
A
- Metabolism of neurotransmitters inhibited
12
Q
Reuptake Blocking
A
- Neurotransmitter reuptake blocked
- Into pre-synaptic neuron
13
Q
Nerve Stimulation
A
- Drug directly stimulates nerve
- Release of more neurotransmitter
14
Q
Parkinson’s Disease
A
- Progressive loss of dopaminergic neurons
- Within substantia nigra of brain
- 70-80% loss
- 5-10 year progression
15
Q
Parkinson’s Symptoms
A
- Tremor (face, hands, arms, legs, jaw)
- Rigidity (joint stiffness/increase muscle tone)
- Bradykinesia (slow movement)
- Masklike face (no expression/limited movement)
- Postural instability (impaired balance)
- Dementia (later stages)
16
Q
Parkinson’s Pathophysiology
A
- Decreased dopamine release
- Inhibit GABA release
- Excess of acetylcholine compared to dopamine
- Increase GABA release
- Excess GABA causes movement issues
17
Q
Etiology Development
A
- Drugs (street drugs produce MPTP compound)
- Genetics (mutation in 4 genes)
- Environmental toxins (pesticides)
- Brain trauma
- Oxidative stress (diabetes induced oxidative damage)
18
Q
Parkinson’s Drug Treatment
A
- Increasing dopamine
- Decreasing acetylcholine
19
Q
Dopamine Increasing Agents
A
- Dopamine replacement
- Dopamine agonist
- Dopamine releaser
- Catecholamine-O-methyltransferase inhibitor
20
Q
Dopamine Replacement (Levodopa/L-DOPA)
A
- Most effective drug treatment
- Effects decrease as disease progresses
- Cross BBB through transport protein
- Converts to dopamine in dopaminergic nerve terminals
- Conversion mediated by decarboxylase brain enzymes
- Reaction sped up by vitamin B6 (pyridoxine)
21
Q
Regular Dopamine
A
- Dose not cross BBB
- Short half-life in blood
22
Q
Adverse Effects of L-Dopa
A
- Nausea & vomiting
- Dyskinesias (involuntary movement)
- Cardiac dysrhythmias
- Orthostatic hypotension
- Psychosis (hallucinations)
23
Q
Peripheral Metabolism of L-Dopa
A
- Majority metabolized in intestine before reaching brain
- Administered with carbidopa
24
Q
Carbidopa with L-Dopa
A
- Decarboxylase inhibitor of peripheral metabolism
- More levodopa reaches brain
- Allows for lower dose of levodopa
- Decreases nausea/vomiting, cardiac dysrhythmias
25
Q
Minimizing Wearing Off of L-Dopa
A
- Shortening dosing interval
- Admin of inhibiting L-DOPA metabolism
- Add dopamine agonist
26
Q
Dopamine Agonist
A
- Activate dopamine receptors on post-synaptic membrane
- Less effective as L-DOPA
- First line treatment for mild symptoms
27
Q
Adverse Effects of Dopamine Agonists
A
- Hallucinations
- Daytime drowsiness
- Orthostatic hypotension