So, how it
possible that the original piece of Ricaurte research, so vaunted by
the US government, trumpeted from every news outlet, and chronically
referred to in prohibitionist literature as proof of the evils of MDMA
was so badly off? Maybe the gods smiled on him and brought him subjects
that simply were not representative of the general population. Maybe
he and his people screwed up somehow. And maybe...maybe he
simply took a 'creative' view towards data collection methods. We may
never know for sure. In the meanwhile, when the minions of prohibition
ecstasy', they will no doubt continue to refer to Ricaurte's work as
their 'proof', ignoring the newer, larger, more sophisticated, and much
more numerous experiments suggesting that changes to the average ecstasy
user's brains from common patterns of use are, at worst, minor and temporary.
Experiment 6: Neuroendocrine
of the long-term effects of MDMA neurotoxicity in lab animals is that
the animals become hyper-sensitive to drugs that activate serotonin receptors.
occurs because when levels of serotonin severely decrease, the brain
increases the number of serotonin receptors to try to compensate. As
a result, when the animals are given serotonin-receptor activating drugs,
the drugs affect them much more strongly than they would animals who's
serotonin systems were undamaged. By measuring levels of a 'stress
hormone' called prolactin in the blood
we can gauge the intensity of
the animal's reaction to serotonin receptor activating drugs, such as
m-CPP (m-chlorophenylpiperazine.) The graph below shows the difference
in reaction to m-CPP in normal monkeys vs. ones that had been given a
neurotoxic dose of MDMA years earlier:
As you can see, the monkeys
who's serotonin systems had been damaged by MDMA had a much larger
stress reaction to the drug. What then was the reaction of human 'ecstasy'
users to this very same test? Not only did they not have an exaggerated
reaction to m-CPP, they actually had slightly less of a stress
reaction than non-ecstasy users:
That they were actually
somewhat less stressed by the drug seems surprising at first...but becomes
less odd when you consider that, by definition, MDMA users are people
who use and like drugs that activate serotonin receptors (in the case
of MDMA, by releasing serotonin.) The 'ecstasy' users also smoked more
pot, which other research has found also reduces the prolactin response
to serotonin receptor activation.
An argument could be made
that the 'ecstasy' users brains might have suffered neurotoxicity
were not sensitized because they had downregulated serotonin receptors
in response to recent drug exposure. However, this argument falls
on several counts. First, the 'ecstasy' users had an average of 14
weeks between their last dose and the test. Rats show complete re-setting
of serotonin receptor densities within 3-4 weeks of their last dose
of MDMA. Although humans are likely to take
more time to recover from a pharmacologically equivalent dose than
14 weeks is somewhat of a stretch; other research has found that users
who had been abstinent for 20 weeks had comparable serotonin receptor
densities to non-users. Secondly, receptor downregulation
requires that the receptors be overactivated in the first place. If
the recreational doses of MDMA used repeatedly in the past by these
individuals were neurotoxic, how was it possible that 'ecstasy' use
had been able to release enough serotonin from non-existing axons to
Ricaurte's great Ecstasy Parkinson's Fraud:
In the fall of 2002
George Ricaurte, the Dark Prince of suspect science, published an article
in the prestigious journal Science that
claimed that a "common recreational
caused severe damage to the dopamine systems of monkeys. (Parkinson's
disease involves the death of dopamine neurons, so extensive damage to
could presumably cause symptoms similar to Parkinson's.) The press and
politicians went mad. Draconian new anti-MDMA laws were passed, including
the infamous RAVE Act, which made it illegal to throw a party if you
"should have known" that some people would be using drugs
at it. MAPS,
which had been on the verge of finally having its MDMA post-traumatic
stress disorder research approved, was stopped cold in the
face of the apparent new evidence of MDMA's horrific dangers.
More than a year
later, facing increasing questions from critics, the house of cards collapsed when Ricaurte
admitted that the experiment never really happened: The
monkeys had actually been given massive doses of methampetamine, not
also admitted that no matter what they had tried, they had been unable
monkey's dopamine systems with real MDMA.
As the saying goes, it's
all over but the shouting. Ricaurte claims the drug manufacturer switched
on two vials (one of methamphetamine, one of MDMA) causing the error.
The manufacturer (RTI) has vigorously
disputed the claim that a switch occurred at their facilities (which
are very tightly run under
D.E.A. oversight.) The study reportedly
cost the American taxpayers $1.3 million. Somebody owes us a refund;
I nominate Ricaurte.
coverage of the scandal (including links to the original article,
the retraction, and reactions from the research community.)
• My letter to Science (the
publisher of the offending article) detailing some of the flaws
in the original claims.
Ecstasy use and mental health.
There's been a
news story claiming that ecstasy use causes depression. The
research this story is based on has apparently never been published,
suggesting that it was of such low quality that even in an age of anti-drug
hysteria no scientific publication felt it was worth printing.
However, the basic finding (that ecstasy users are more likely to have
emotional problems) does in fact appear to be true.
In a large longitudinal German
study (tracking about 2,500 people over time) it was found that, at the
end of the study, 68% of those reporting having used "ecstasy" at
least once also reported having suffered from a DSM-IV
disorder at some point in their lives. (DSM-IV
is a mental health diagnostic manual.) However, the researchers report
that in about 90% of these cases, the person was diagnosed with a mental
disorder before their first use of 'ecstasy.' It is
likely that MDMA (and other drug use) can
trigger or worsen psychiatric problems, but
in at least the vast majority of cases, psychiatric problems are more
likely to be the cause of the drug use, not the other way around. 'Ecstasy'
users, statistically speaking, are not normal to start with.
• Visit the Mental Health page for more information.
know people that are stupid/emotionally unstable from using 'ecstasy'...doesn't
mean they've been brain damaged?!"
Not necessarily. The nervous
system tries to correct for unusual levels of activity, often by 'turning
the volume down' (or up) on different systems. In the case of coffee
drinkers, your brain makes itself less sensitive to caffeine, creating
cases, mild dependence.) If you take a lot of acetaminophen, your body
eventually works to counteract it, which can lead to 'rebound' headaches
(the headache coming
back if you stop taking acetaminophen.) This phenomenon of your brain
trying to compensate for unusual factors (such as drugs) is called neuroadaptation,
and is one cause of drug tolerance (needing more to have the same effect)
and physical dependence. Neuroadaptation is not damage!
It is a constant, normal, and entirely controlled process by which
your brain tries to keep itself running smoothly.
can be manipulated in useful ways: SSRI antidepressants like Prozac,
Zoloft, Paxil, etc. work partly by getting your brain to change its
sensitivity to serotonin (for those drugs the process is somewhat slow,
which is why it takes several
weeks for an SSRI to become fully effective against depression.)
However, in the case of recreational
drug use, this effect is almost always disruptive: You take a drug for
a brief period, your brain tries to compensate, and then when the drug
is gone your brain is off-balance again, now over-compensating. It will
return to normal, but the process can take days, weeks, in some cases
even months. In the case of MDMA, your brain makes itself less sensitive
to serotonin to try to compensate for all the serotonin the drug releases.
Fully re-setting its sensitivity levels after even a single use of MDMA
can take weeks, even months from a very high dose. If you use MDMA frequently,
your brain doesn't have enough time to re-set and gets pushed further
serotonin sensitivity. In extreme cases, this can apparently lead to
users becoming seriously depressed, anxious, unmotivated, poor memories,
It's quite understandable
that people are afraid of brain damage when they experience this sort
of mental disruption; the average person has never been told that there
were any other possible explanations, in spite of virtually all of us
being familiar with the basic phenomenon in the form of 'needing that
first cup of coffee in the morning to get going' and the like. My position
is not that people don't get seriously screwed up by
frequent use of MDMA; only that the cause is unlikely to be actual permanent
a break from use of a few months, even the most severely 'e-tarded' user
should find themselves greatly improved as the brain slowly returns
normal 'volume settings.' (For more information and an animation of one
process of neuroadaptation, visit MDMA At Work.)
I absolutely believe that
MDMA can be neurotoxic in humans. There's just no
reason to believe that it is at a sane dosage/under normal circumstances,
and your odds can be greatly improved with a little common sense: Don't
mix drugs, be aware of overheating dangers,
and take some antioxidants.
What I would
consider safe usage of MDMA?
• A single dose. Taking
multiple full doses in an evening may not be safe. As a single dose,
even doses high enough to just about knock you on your ass (in the 2
mg/kg range) are probably safe. ('Safe' in the sense that
driving a car is safe; relative, not absolute safety.)
• A safe environment. That
means either moderate ('room temp') air temperatures or avoiding high
levels of activity (dancing.)
• No drug mixing, including
alcohol. Not all drugs can increase risk, but unless you're sure you
know what you're
doing, it's best not to be on other drugs while high on MDMA.
MDMA-related injuries and deaths
are in most cases actually overheating injuries and deaths. MDMA
does not normally cause significant increases in body temperature in
humans; a significant increase in body
temp is abnormal
and should be treated immediately.
The role of overheating in
MDMA neurotoxicity can hardly be exaggerated; no
experiment has ever produced neurotoxicity at any dose of MDMA
at normal human body temperature. In the infamous Ricaurte "Ecstasy
Parkinsonism" monkey experiment, his animals reached body temperatures
of as high as
107F. More typically, experimental animals that develop MDMA neurotoxicity
reach body temperatures of about 39C (103F). Although the exact mechanisms
of MDMA neurotoxicity are at best imperfectly understood, damage is
clearly a result of the combination of the unusual strain placed on the
neurons by drug exposure being greatly amplified by overheating.
I do not anticipate human neurotoxicity at any likely voluntarily taken
dose of MDMA in the absence of significant and prolonged
On a personal note, I have
used MDMA in the distant past when I had no idea what the risks might
be. I have also continued to use on rare occasion now that I know a
great deal about what the risks might be. I'm willing to bet my brain
that I'm right about (reasonable levels) of MDMA use causing no lasting
harm, and I do so with complete confidence.
It has been suggested that,
as an unabashed former and sometimes-current user of MDMA, I have a
bias. That's certainly true, but it may not be what you would expect.
As somebody who may use this drug again in the future, the question
of safety is something I don't take lightly. Overlooking evidence that
future use might damage my brain just because I find the drug enjoyable
would be nothing short of insanity; I take the health of my brain very
seriously and I'm not that fond of any drug. Whether my decision is
an informed one or not, you'll have to decide for yourself.
One reader expressed the opinion
that I might be trying to downplay the risks 'to justify my sinful
use.' To be honest, the thought had never crossed my mind (either that
drug use was wrong, or that I needed to justify myself.) I've used
because I'm smarter and better educated than the average drunk, and
thus have some better ideas of how to waste a weekend. It's really
simple. They go out and get drunk, once in a great while I get high.
I'm taking smaller medical risks, less likely to become addicted,
and frankly having a much better time.
Still, one might ask, why admit
to drug use at all when that could prejudice readers? Surely it would
be wiser from a public relations perspective to play the impartial academic,
by accident and with no particular interests?
I'm honest about it for two reasons:
First, because it's the truth, and most readers would guess anyway.
Secondly, because it's time people 'came out of the closet' about drug
use. For too long the public's opinion of what drug users are like
been extraordinarily colored by the social fringes who had nothing
to lose from open drug use and addicts who were so far gone they could
no longer avoid being noticed. The public never sees the tens of millions
of perfectly decent, honest, employed, tax-paying citizens who keep
quiet about drugs because they've reached a social position where they
have something to lose. And so, yes, I inhaled. I enjoyed it, no harm
came of it...and I'll do it again if I wish. Is this not the right
of any competent adult in a free society?
Origin of the Species:
leading to this final document involved a comprehensive review of English-language
MDMA research from the 1950s to present; well over a thousand
journal articles detailing numerous animal and human experiments, field
reports from doctors, opinions of experts, etc. 'Library research'
of this sort is a rather thankless and tedious task, but when you get
you've really gotten to the end; no opinion is left unconsidered,
no research left unexamined. I compiled my notes, discussed and argued
with other academics, contacted researchers for more information
in some cases, etc. This document expresses and makes the case for
the final opinion that my research brought me to: That moderate recreational
use of MDMA does not present a credible risk for neurotoxicity. It
is not a comprehensive discussion of the totality
of the research (although most brain scan
work, pro and con, has been included.)
Conspicuously lacking is detailed coverage
of the numerous generic sorts of 'ecstasy users not as mentally sharp'
type of research.
This was not done as a way to avoid evidence against my position;
rather it is because the quality of such research has been so consistently
poor as to not merit detailed examination. The typical work in this
category makes the following chain of assumptions:
1. People who use 'ecstasy' were (prior to their drug use) just
like non-drug users.
2. The people
we recruit are representative of the larger user population.
No other drugs that the volunteers use will affect results.
are no differences in sleep patterns, sub-clinical psychiatric
or any other environmental factors that could affect test
5. Any differences that are found must be due to permanent damage.
Neuroadaptation (such as the brain scan research amply demonstrates
the existence of) will not be considered.
Assumption 1 has been disproven; pre
drug-use rates of mental illness in ecstasy users are higher than
those of non-drug
users as well as users of other categories of drugs. Assumption 2 cannot
easily be disproven, but is unlikely to be true. Assumption 3 is disproven
by the unremarkable fact that when concurrent use of marijuana is
controlled for, differences in cognitive performance (such as word
recall) mostly or entirely vanish. 4. Ravers (attendees of all-night
dance parties) are usually the recruitment pool for volunteers, which
brings a rather unlikely assumption of otherwise equivalent lifestyles
between ecstasy users and non-users. 5. That MDMA causes transient
disruptions of memory is well established anecdotally, and should be
inferred from research identifying neuroadaptive changes in available
serotonin receptor densities in both experimental animals and humans
following recent MDMA exposure. Researchers in the 'ecstasy users have
worse memories' field tend to ignore this problem. Those that do make
control this effect usually do no more than ask volunteers not to use
for two weeks and give urine test for drugs the day of testing. However,
all research indicates that MDMA can subtly affect the mind for at
least 3-4 weeks, and urine drug tests only detect use within the past
A less obvious problem in such human
research is subject bias. When testing a new medication, you can't
let the people who you're testing it on know if they're getting the
real drug or a sugar pill, because expectations can produce a powerful
placebo effect; people who expect to feel better inevitably do feel
better. Any sort of expectation of what the results will be by the
test subjects will throw off those same results. This sort of problem
is especially great when testing drug users for cognitive
in the control group or not, they probably have some idea of what the
researchers expect the result to be. (For instance, just about anybody
you recruit for an MDMA study knows that they are expected to have
memory problems.) How can you control for this sort of bias? The honest
answer is you can't, although you can at least try not to promote a
bias. The most flagrant act of fraud I've seen in this category was
a researcher who, before testing some 'ecstasy' users
to see if they were different from non-users, told them that their
MDMA use caused
untreatable brain damage that would impair their performance. It takes
balls of steel to deliberately shape experimental results like that,
but not everybody working in this field has a high sense of scientific
In the end, I hold a dim view of the
genre. Besides, why try to guess at serotonergic damage from behavior
when we have perfectly capable brain-scanning technology to directly
examine the serotonin system? For
these reasons of both quality and directness of the measurement technique
this page almost exclusively examines brain scan work. At the end
of the day, I am wholly unmoved when Billy Bob the psychologist publishes
an article claiming evidence of neurotoxicity because his ecstasy-using
volunteers were not identical to his non-drug using volunteers. There
is an ocean
must be bridged to make such conclusions credible, especially in light
of the strong evidence of no permanent structural changes
brains. The quality of retrospective human research has, however, been
increasing over the years; with luck, the future may bring more
 Ricaurte GA, DeLanney LE, Irwin
I, Langston JW "Toxic effects of MDMA on central serotonergic
neurons in the primate: importance of route and frequency of drug administration" Brain
Res , 1988; 446(1):165-8. Abstract.
 Ricaurte GA, Yuan J, McCann UD "MDMA
('Ecstasy')-Induced Serotonin Neurotoxicity: Studies in Animals",
Neuropsychobiology, 2000; 42(1):5-10. Abstract.
 Yuan J, Cord BJ, McCann UD, Callahan
BT, Ricaurte GA "Effect of depleting vesicular and cytoplasmic
dopamine on MDMA neurotoxicity", J Neurochem, 2002; 80(6):960-9.
 Sprague JE, Nichols DE "Inhibition
of MAO-B protects against MDMA-induced neurotoxicity in the striatum",
Psychopharmacology (Berl), 1995; 118(3):357-359. Abstract.
 Shankaran M, Yamamoto BK, Gudelsky
GA "Ascorbic Acid Prevents 3,4-MDMA Induced Hydroxyl Radical Formation
and the Behavioral and Neurochemical Consequences of the Depletion of
Brain 5-HT", Synapse 2001; 40:55-64. Abstract
 Bolla KI, McCann UD, Ricaurte GA
"Memory impairment in abstinent MDMA "Ecstasy" users",
Neurology, 1998; 51(6):1532-7. Abstract.
 Simon NG, Mattick RP "The impact
of regular ecstasy use on memory function", Addiction,
2002; 97(12):1523-9. Abstract.
 Chang L, Grob C, Ernst T, Itti L,
Mishkin F, Jose-Melchor R, Poland RE "Effect of ecstasy (MDMA)
on cerebral blood flow: a co-registered SPECT and MRI study", Psychiatry
Research (Neuroimaging Section), 2000; 98:15-28. Abstract.
 Gamma A, Buck A, Berthold T, Vollenweider
FX "No Difference in Brain Activation During Cognitive Performance
Between Ecstasy (3,4-MDMA) Users and Control Subjects: A [H2(15)O]-PET
study", J Clin Psychopharmacol, 2001; 21(1):66-71. Abstract.
 McCann UD, Szabo Z, Scheffel U,
Dannals RF, Ricaurte GA "Positron emission tomographic evidence
of toxic effect of MDMA ("Ecstasy") on brain serotonin neurons
in human beings", Lancet 1998; 352(9138):1433-7. Abstract.
 Vollenweider FX, Gucker P, Schönbächler
R, Kamber E, Vollenweider-Scherpenhuyzen MFI, Schubiger G, Hell D "Effects
of MDMA on 5-HT uptake sites using PET and [11C](+)McN-5652 in humans"
Conference of the German Society for Psychiatry, Psychotherapy and
Neuromedicine (2000). Abstract
 Semple DM, Ebmeier KP, Glabus MF,
O'Carroll RE, Johnstone EC "Reduced in vivo binding to the serotonin
transporter in the cerebral cortex of MDMA ("ecstasy") users"
Br J Psychiatry, 1999; 175:63-9. Abstract
 Reneman L, Lavalaye J, Schmand B,
de Wolff FA, van den Brink W, den Heeten GJ, Booij J "Cortical
serotonin transporter density and verbal memory in individuals who stopped
taking MDMA: Preliminary findings", Archives of General Psychiatry,
2001; 58(10):901-906. Abstract.
 Reneman L, Booij J, de Bruin K,
Reitsma JB, de Wolff FA, Gunning WB, den Heeten GJ, van den Brink W
"Effects of dose, sex, and long-term abstention from use on toxic
effects of MDMA (ecstasy) on brain serotonin neurons" Lancet
2001; 358(9296):1864-1869. Abstract.
 Scheffel U, Szabo Z, Mathews WB,
Finley PA, Dannals RF, Ravert HT, Szabo K, Yuan J, Ricaurte GA "In
Vivo Detection of Short- and Long-Term MDMA Neurotoxicity--A Positron
Emission Tomography Study in the Living Baboon Brain", Synapse
1998; 29(2):183-92. Abstract.
 Hatzidimitriou G, McCann UD, Ricaurte
GA "Altered serotonin innervation patterns in the forebrain of
monkeys treated with MDMA seven years previously: Factors influencing
abnormal recovery" J Neurosci 1999; 19(12):5096-107. Abstract.
 Buchert R, Thomasius R, Nebeling
B, Petersen K, Obrocki J, Jenicke L, Wilke F, Wartberg L, Zapletalova
P, Clausen M "Long-Term Effects of "Ecstasy" Use on Serotonin
Transporters of the Brain Investigated by PET", J Nucl Med
2003; 44: 375-84. Abstract.
 Lieb R, Schuetz CG, Pfister H, von
Sydow K, Wittchen H "Mental disorders in ecstasy users: a prospective-longitudinal
investigation." Drug Alcohol Depend 2002; 68: 195-207.
 Schmidt CJ "Acute and long-term
neurochemical effects of methylenedioxymethamphetamine in the rat" NIDA
Res Monogr, 1989; 94:179-95. Abstract.
 Bai F, Lau SS, Monks TJ "Glutathione
and N-acetylcysteine conjugates of alpha-methyldopamine produce serotonergic
neurotoxicity: possible role in methylenedioxyamphetamine-mediated
neurotoxicity." Chem Res Toxicol, 1999; 12(12):1150-7. Abstract.
 Colado MI, Green AR "The spin trap
reagent alpha-phenyl-N-tert-butyl nitrone prevents 'ecstasy'-induced
neurodegeneration of 5-hydroxytryptamine neurones" Eur J Pharmacol,
1995; 280(3):343-6. Abstract.
 Bleh, ref has gone missing...try
again in a month or two if you're comitted. :-)
 O'Shea E, Easton N, Fry JR, Green
AR, Marsden CA "Protection against 3,4-methylenedioxymethamphetamine-induced
neurodegeneration produced by glutathione depletion in rats is mediated
by attenuation of hyperthermia" Journal of Neurochemistry,
2002; 81(4):686-695. Abstract.
 Meyer A, Mayerhofer A, Kovar K,
Schmidt W "Enantioselective metabolism of the designer drugs 3,4-methylenedioxymethamphetamine
('ecstasy') and 3,4-methylenedioxyethylamphetamine ('eve') isomers
in rat brain and blood" Neuroscience Letters, 2002; 330(2):193-197. Abstract.
 Lim HK, Foltz RL "In vivo and in
vitro metabolism of 3,4-(methylenedioxy)methamphetamine in the rat:
identification of metabolites using an ion trap detector" Chem
Res Toxicol, 1988; 1(6):370-8. Abstract.
 Ricaurte GA, Yuan J, Hatzidimitriou
G, Cord BJ, McCann UD "Severe Dopaminergic Neurotoxicity in Primates
After a Common Recreational Dose Regimen of MDMA (“Ecstasy”)"
Science, 2002; 297:2260-2263. Abstract.
 Reneman L, Booij J, Lavalaye J,
de Bruin K, Reitsma JB, Gunning B, den Heeten GJ, van Den Brink W "Use
of amphetamine by recreational users of ecstasy (MDMA) is associated
with reduced striatal dopamine transporter densities: a [123I]beta-CIT
SPECT study-- preliminary report" Psychopharmacology (Berl) , 2002;
 Mintzer S, Hickenbottom S, Gilman
S "Parkinsonism after taking ecstasy" N Engl J Med,
1999; 340(18):1443. Abstract.
 1999 Correspondence from The
New England Journal of Medicine, Vol 341, No. 18. Link.
 de la Torre R, Farre M, Roset PN,
Hernandez Lopez C, Mas M, Ortuno J, Menoyo E, Pizarro N, Segura J, Cami
J "Pharmacology of MDMA in humans", Annals of New York
Academy of Sciences 2000; 914:225-37. Abstract
 Liechti ME, Vollenweider FX "Acute
psychological and physiological effects of MDMA ("Ecstasy")
after haloperidol pretreatment in healthy humans" Eur Neuropsychopharmacol
2000; 10(4):289-95. Abstract
 Schmidt CJ "Neurotoxicity
of the psychedelic amphetamine, methylenedioxymethamphetamine" J Pharmacol
Exp Ther, 1987; 240(1):1-7. Abstract.
 Rattray, Baldessari,
Gobbi, Mennini, Samanin, and Bendotti "p-Chlorophenylalanine Changes
Serotonin Transporter mRNA Levels and Expression of the Gene Product"
J of Neurochem, 1996; 67(2); 463-472. (Abstract unavailable.)
Download as PDF.
G, Tsai EH McCann U D, Ricaurte GA "Altered prolactin response
to M-chlorophenylpiperazine in monkeys previously treated with 3,4-methylenedioxymethamphetamine
(MDMA) or fenfluramine" Synapse, 2002; 44(1):51-57. Abstract.
 McCann UD, Eligulashvili
V, Mertl M, Murphy DL, Ricaurte GA "Altered neuroendocrine and
behavioral responses to m-chlorophenylpiperazine in 3,4-methylenedioxymethamphetamine
(MDMA) users" Psychopharmacology (Berl), 1999; 147(1):56-65.
E, Becker S, Pelz S, Tuchtenhagen F, Daumann J "Neuroendocrine
abnormalities in recreational ecstasy (MDMA) users: is it ecstasy or
cannabis?" Biol Psychiatry, 2002; 51(9):766-769. Abstract.
 Scheffel U, Lever
JR, Stathis M, Ricaurte GA "Repeated administration of MDMA causes
transient down-regulation of serotonin 5-HT2 receptors" Neuropharmacology,
1992; 31(9):881-93. Abstract.
 Reneman L,, Endert
E, de Bruin K, Lavalaye J, Feenstra MG, de Wolff F, Booij J "The
acute and chronic effects of MDMA (“Ecstasy”) on cortical
5-HT 2A receptors in rat and human brain" Neuropsychopharmacology,
2002; 26:387–396. Abstract.