Drugs, Lec 19: 03/17/2014
*7 mins late
Boost dopamine by giving Ldopa.
Stimulate dopamine D2 receptor postsynapticallly.
Idiopathic Parkinson’s has 0 genetic concordance. Unknown cause.
Principal symptom of Parkinson’s: akinesia. Lack of movement.
Ldopa: Involuntary movements is a side effect.
Nerve terminals in the dorsal striatum. First thing that gets affected in
Retrograde degeneration all the way back to the SN neurons.
Age: reason for Parkinson’s degeneration. Incidence rate of Parkinson’s in the course of a life time:
Enzyme converting MAO is what converts MPPP to MPTP. Normal function is to clean
excess NT from synaptic cleft. 3 MO’s are: DA, Norepi, and serotonin.
MAOI’s: Pargyline and deprenyl. Boost norepi and serotonin. Block the enzyme.
Quiz on Wednesday!
80% or greater depletion of DA to show Parkinson’s symptoms.
MAOI only help a little in Parkinson’s patients, why? DA nerve terminals are
gone. Very little dopamine left to protect. What can you do? Go to postsynapse, use
direct DA D2 agonist stimulation. Replace all the missing DA by replacing the actions.
What works to treat Parkinson’s? Nonmedical ways.
DBS: deep brain stimulation. But can overstimulate, get depolarization blockade, overestimate the
neurons until they shut off. Really inactivates the neurons, not good.
Can also destroy the subthalamic nucleus, and that improves voluntary movements.
End of Parkinson’s Now for cocaine and crystal meth:
Naturally occurring as a plant alkaloid (basic) from the c