[MDMA]MDMA Neurochemistry, drugs
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(An MDMA Neurochemistry Slideshow)
Each slide in this slide-show is rated for its level of technicality with the word BASIC,
INTERMEDIATE, or ADVANCED.
Generally, the slideshow progresses from basic to advanced. The advanced slides should not
be too difficult to understand if you have gone through the previous ones.
The second part of this slideshow is all about MDMA neurotoxicity, including up-to-date
research and current theories.
This Slideshow was created by Emanuel Sferios. Feel free to reproduce any or all of it at will.
All we ask is that you credit Emanuel and DanceSafe. Emanuel can be contacted at:
emanuelsferios@dancesafe.org
Slide #1 (BASIC)
This is a model of a typical human brain, showing some of the basic brain areas. You don't
need to memorize them all. This is just a warm-up slide to get you started.
Slide #2 (BASIC)
This is a model of a typical brain cell, or neuron. Your brain contains billions of brain cells. A
brain cell consists of a cell body, which stores the DNA, dendrites which receive chemical signals
from other cells, and an axon, which carries an electrical signal from the cell body to the axon
terminals. The axon terminals contain chemicals, called "neurotransmitters," which are released
in order for the cell to communicate with nearby cells.
Serotonin is a neurotransmitter, and some brain cells have axons that contain only serotonin.
These are called "serotonin neurons." Other brain cells produce and release different
neurotransmitters, like dopamine or norepinephrine, and some produce and release more than one
neurotransmitter. However, your serotonin cells only produce and release serotonin.
Slide #3 (BASIC)
Here you can see how the axon terminals, which contain serotonin, lie very close to the
dendrites of other, nearby neurons. Notice the gap between the axon terminal of the
serotonin neuron and the dendrites of the next neuron. This gap is called the "synapse" and is
where the serotonin gets released. Soon we will look at the synapse up close, and see what
happens when ecstasy causes large amounts of serotonin to be released there. But first, let's
look at how serotonin cells are distributed throughout your brain.
Slide #4 (BASIC)
Most serotonin cells (
in red
) begin in a specific area of the the brain stem called the "raphe
nuclei." Their dendrites and cell body's are located here, and they have very long axons that
extend into every other part of the brain. Serotonin axons are much denser and have many
more tree-like branches than we were able to show in this drawing. They are also much
longer than any diagram can easily depict. If you were to stretch out a serotonin neuron on a
table in front of you, it might be a foot long, but you still wouldn't be able to see it because it
would be so thin. Most people think of brain cells as shorter and confined to particular brain
regions (
in blue
). While some brain cells are like this, this is not the case with serononin cells.
No wonder serotonin plays such an important role in so many brain functions, such as the
regulation of mood, heart-rate, sleep, appetite, pain and other things.
Slide #5 (BASIC)
This is an actual photograph of serotonin cells (mostly axons) in a rat's brain. Notice the tree-
like branching of the axons. The dark spaces around the serotonin cells are actually densely
filled with other brain cells. You can't see them in this picture, however, because only the
serotonin cells were stained to make them visible.
Slide #6 (BASIC)
Ecstasy causes your serotonin neurons (
yellow
) to release large amounts of serotonin (
the
little red dots
), which are stored in the axon terminals. This massive serotonin release is
responsible for the primary subjective effects of MDMA. MDMA also releases the
neurotransmitters dopamine and norepinephrine. The role of these two neurotransmitters in the
MDMA effect will be explained later in the slideshow.
Slide #7 (BASIC)
Inside the axon terminal are small vesicles that contain serotonin molecules. When an
electrical charge comes down the axon, these vesicles merge with the outer membrane of the
axon terminal and release serotonin into the synapse. We are going to take a closer look at
this, because there is a lot that goes on in the synapse. But let's first look at a 3-d drawing of
some vesicles inside a serotonin axon.
Slide #8 (BASIC)
This is an artists rendition of the view inside a serotonin axon terminal. The vesicles float
around scooping up serotonin, and when directed to by an electrical current coming down
the axon, they merge with the membrane and release the serotonin into the synapse.
Slide #9 (BASIC)
Moving in a little closer to the synapse, we can see some serotonin molecules floating around.
We also see some serotonin reuptake transporters on the membrane of the axon terminal, as
well as receptors on the dendrite of the nearby neuron. In order to understand how MDMA
works in the brain, and why it produces the effects it does, you need to know what these
reuptake transporters and receptors do. But first, just for the fun of it, let's look at an actual
photograph of a synapse...
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