Module 14a Flashcards
Stud of how drugs affect the function of the CNS.
Neuropharmacology
There are many disorders in the CNS, and most of them have a component that is mediated by a ________ imbalance. We treat this imbalance with _____.
Unfortunately, these only treat the ________ of disease, not the ______.
biochemical
drugs
symptoms
cause
Cells in the brain that act to process and transmit signals and information.
Neurons
The start of information transfer in the neuron begins at the ________, which receives a signal from another neuron.
dendrite
The resting membrane potential of cells is approximately ____. This means that the inside of the cell is _______ with respect to the outside.
-70mV
negative
During depolarization of a neuron, positively charged ____ ions enter the cell through these.
Na+
voltage-gated Na+ channels
During repolarization of a neuron, these ions leave the neuron.
potassium
Only a few potassium channels are open. Potassium can freely move in and out of cells. The membrane potential does not change.
Resting potential.
IF a depolarizing stimulus is received, it opens a few sodium channels. This allows sodium to enter the cell, until this point is reached.
Threshold
If threshold is achieved, other sodium channels open and sodium rushes in. the membrane potential increases further.
rising phase
Sodium channels close and potassium channels open. Potassium rushes out of the cell and the membrane potential decreases. As the membrane potential approaches resting potential even more potassium channels open.
Falling phase
The membrane potential undershoots the RMP due to excess potassium leaving the cell
Hyperpolarization
Describe the transmission of the chemical signal from one neuron, to another.
The action potential reaches the pre-synaptic nerve terminal.
This induces calcium influx into the neuron.
Calcium causes vesicles to fuse with the pre-synaptic membrane, and release NTs into the synpatic cleft.
NTs travel through the synaptic cleft and bind to receptors on the post-synaptic membrane, inducing an action potential in the post-synaptic neuron
What are the major NT classes?
Monoamines (Epinephrine, NE, Dopamine, Serotonin)
Amino acids (Glutamate, GABA, aspartate, glycine)
Other (ACh)
What NTs fall in the monoamine class?
Serotonin, Epinephrine, NE, Dopamine
What NTs fall in the amino acid class?
Glutamate, GABA, aspartate, glycine
What NT falls in the other class?
ACh (acetylcholine)
Excitatory amino acid NTs.
Glutamate, aspartate
Inhibitory amino acid NTs
GABA, glycine
5 ways in which drugs that treat CNS disorders may act.
Replacement Agonists/Antagonists Inhibiting NT breakdown Blocking reuptake Nerve stimulation
The drug acts to replace NTs that are low in diseases
Replacement
A drug that directly binds to receptors on the post-synaptic membrane
Agonists/Antagonists
NT metabolism is inhibited
Inhibiting NT breakdown
NT reuptake into the pre-synaptic membrane is blocked
Blocking reuptake
The drug directly stimulates the nerve causing it to release more NT
Nerve stimulation
Parkinson’s was first described in 1817 by ______ Parkinson.
James
PD is caused by a progressive loss of _________ neurons in the ________ _______ of the brain.
dopaminergic
substantia nigra
Is progressive loss of dopaminergic neurons a normal process of aging?
yes, however in PD, this number is very elevated