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Una D. Mccann

National Institute of Mental Health

9 papers in the library · 1,973 citations · publishing 1991-2007

Papers

Altered Serotonin Innervation Patterns in the Forebrain of Monkeys Treated with (±)3,4-Methylenedioxymethamphetamine Seven Years Previously: Factors Influencing Abnormal Recovery

Journal of Neuroscience June 15, 1999 George Hatzidimitriou, Una D. Mccann, George A. Ricaurte 338 citations

Seven years after treatment with MDMA (Ecstasy), squirrel monkeys still showed abnormal brain serotonin innervation patterns, though deficits in some regions were less severe than those observed at 18 months. No loss of serotonin nerve cell bodies in the rostral raphe nuclei was found, indicating that the abnormal patterns are not due to the loss of a particular cell group. Factors influencing recovery of injured serotonin axons include the distance of the affected terminal field from the raphe nuclei, the degree of initial injury, and possibly proximity to myelinated fiber tracts. Additional studies are needed to understand these factors and whether findings apply to humans.

3,4‐Methylenedioxymethamphetamine (MDMA, “Ecstasy”): pharmacology and toxicology in animals and humans

Addiction May 1, 1994 Thomas Steele, Una D. Mccann, George A. Ricaurte 295 citations

MDMA (Ecstasy) produces a mix of stimulant and psychedelic effects mediated by brain monoamines, especially serotonin and dopamine. It also shows toxic activity toward brain serotonin neurons in animals, including non-human primates, at doses close to those used by humans. Whether MDMA is neurotoxic in humans remains under investigation, but documented adverse effects include systemic complications and neuropsychiatric consequences involving mood, cognition, and anxiety. Because MDMA use is restricted, retrospective clinical observations are a primary source of human data. This article reviews MDMA's behavioral pharmacology and toxicology to help clinicians recognize MDMA-related syndromes and understand serotonin's role in health and disease.

(±)3,4-Methylenedioxymethamphetamine (‘Ecstasy’)-Induced Serotonin Neurotoxicity: Studies in Animals

Neuropsychobiology January 1, 2000 George A. Ricaurte, Jie Yuan, Una D. Mccann 291 citations

MDMA, or 'Ecstasy', is a potent and selective neurotoxin for brain serotonin neurons in animals, as shown by neurochemical, neuroanatomical, and functional measures. New data indicate that MDMA reduces levels of the type 2 vesicular monoamine transporter, further supporting its serotonin neurotoxic potential. Using interspecies scaling, the authors demonstrate that dosages of MDMA known to be neurotoxic in animals fall squarely within the range used by recreational human users, countering the argument that animal dosages are too high to be relevant.

(±)3,4-Methylenedioxymethamphetamine (‘Ecstasy’)-Induced Serotonin Neurotoxicity: Clinical Studies

Neuropsychobiology January 1, 2000 Una D. Mccann, Victoria Eligulashvili, George A. Ricaurte 192 citations

MDMA (Ecstasy) is a brain serotonergic neurotoxin in animals, including nonhuman primates. Recreational doses overlap with those causing serotonin neurotoxicity in animals. Human MDMA users show selective decreases in cerebrospinal fluid 5-hydroxyindoleacetic acid and brain serotonin transporters, similar to neurotoxicity seen in nonhuman primates. Functional abnormalities possibly related to serotonin injury include cognitive deficits, altered sleep architecture, altered neuroendocrine function, altered behavioral responses to serotonin-selective drugs, and increased impulsivity. Further animal, longitudinal, and epidemiological studies are needed to confirm these findings and assess whether users face increased risk of neuropsychiatric illness with age.

RETRACTED: Severe Dopaminergic Neurotoxicity in Primates After a Common Recreational Dose Regimen of MDMA ("Ecstasy")

Science September 27, 2002 George A. Ricaurte, Jie Yuan, George Hatzidimitriou et al. 179 citations

The recreational drug MDMA (ecstasy) is widely believed to selectively damage serotonin neurons in animals and possibly humans. However, nonhuman primates given several sequential doses of MDMA—a pattern similar to human use—developed severe damage to brain dopamine neurons, along with milder serotonin damage. This dopamine loss was linked to increased vulnerability to movement problems. The findings suggest that recreational MDMA users may unknowingly risk developing neuropsychiatric disorders related to dopamine or serotonin deficiency, either as young adults or later in life.

Lasting Neuropsychiatric Sequelae of (??)Methylenedioxymethamphetamine (???Ecstasy???) in Recreational Users

Journal of Clinical Psychopharmacology October 1, 1991 Una D. Mccann, George A. Ricaurte, Domenic A. Ciraulo 137 citations

Two people who took large doses of MDMA, a recreational amphetamine analog, developed long-lasting neuropsychiatric syndromes. These cases suggest that MDMA, which is known to damage serotonin neurons in animals, may also cause harmful effects in humans. The evidence indicates that ingesting large amounts of MDMA can lead to lasting adverse functional consequences in vulnerable individuals.

Persistent Effects of (±)3,4-Methylenedioxymethamphetamine (MDMA, “Ecstasy”) on Human Sleep

SLEEP September 1, 1993 Richard P. Allen, Una D. Mccann, George A. Ricaurte 113 citations

MDMA, a recreational drug that damages serotonin neurons in animals, is linked to persistent sleep disturbances in humans. Comparing all-night sleep recordings of 23 MDMA users with 22 matched controls, MDMA users averaged 19 minutes less total sleep and 23.2 minutes less non-REM (NREM) sleep, primarily due to 37 minutes less stage 2 sleep. No significant differences appeared in stages 1, 3, or 4. While the cause—whether serotonin neurotoxicity—remains unknown, the findings suggest MDMA use can lead to lasting changes in brain structures governing sleep.

Effects of (±) 3,4-Methylenedioxymethamphetamine (MDMA) on Sleep and Circadian Rhythms

The Scientific World JOURNAL January 1, 2007 Una D. Mccann, George A. Ricaurte 52 citations

Abusing stimulant drugs like MDMA disrupts sleep-wake patterns because they promote arousal and prevent sleep. MDMA can also damage brain serotonin neurons in animals and possibly humans, and serotonin helps regulate sleep and circadian rhythms. People with MDMA-induced serotonin damage may develop chronic sleep and circadian problems, which could contribute to other issues like memory disturbances seen in abstinent users. This review examines preclinical and clinical studies on how prior MDMA exposure affects sleep, circadian activity, and the circadian pacemaker, identifies knowledge gaps, and suggests future research directions.