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Iain S. Mcgregor

University of Sydney

3 papers in the library · 113 citations · publishing 2007-2021

Papers

MDMA, methamphetamine and their combination: possible lessons for party drug users from recent preclinical research

Drug and Alcohol Review January 1, 2007 Kelly J. Clemens, Iain S. Mcgregor, Glenn E. Hunt et al. 55 citations

The substituted amphetamines MDMA (Ecstasy) and methamphetamine (METH, ice, speed) are increasingly popular among party-drug users. Human studies of their acute and long-term adverse effects are often ambiguous due to confounding factors. Animal models show that intravenous METH is a potent reinforcer, while MDMA enhances social behavior. Brief exposure to either drug can cause long-term reductions in dopamine, serotonin, and noradrenaline in the brain and alter receptor and transporter proteins, though whether this reflects neurotoxicity remains unclear, especially for MDMA. Lasting changes in social behavior, anxiety, depressive symptoms, and memory have been observed in rats, matching some human findings. MDMA/METH combinations may produce greater adverse effects than either drug alone, a concern given that party drug users may frequently encounter this combination.

Neural correlates of MDMA (“Ecstasy”)-induced social interaction in rats

Social Neuroscience June 21, 2008 Murray R. Thompson, Glenn E. Hunt, Iain S. Mcgregor 48 citations

MDMA (Ecstasy) produces feelings of love and closeness in humans and prosocial effects in animals. In male Wistar rats, a moderate dose (5 mg/kg) increased social interaction, specifically general investigation of other rats while decreasing anogenital sniffing. Analysis of neural activation across 39 brain regions showed that MDMA given in a social context caused considerably greater brain activation than the same dose given to solitary rats. Six brain regions—including the caudate-putamen, medial preoptic area, paraventricular thalamic nucleus, central amygdala, ventromedial hypothalamic nucleus, and medial amygdala—showed augmented activation in the social-MDMA group. The nucleus accumbens, ventral tegmental area, and periaqueductal grey were activated only when MDMA was combined with social interaction. These findings suggest MDMA modulates neural circuits regulating affiliative behavior, possibly via oxytocin.

Psilocybin as a Novel Pharmacotherapy for Treatment-Refractory Anorexia Nervosa

OBM Neurobiology June 24, 2021 Sarah-Catherine Rodan, Phillip Aouad, Iain S. Mcgregor et al. 10 citations

Anorexia nervosa (AN) has high mortality and treatment costs, and cognitive behavioural therapy (CBT) achieves remission in at most 50% of adults. Drop-out and relapse rates are high, and no approved pharmacological treatments exist. Over the past two decades, research into classic psychedelics (LSD, 5-MeO-DMT, DMT, and psilocybin) shows that one or two exposures can produce lasting reductions in anxiety and depression, which are the most common co-morbid psychiatric symptoms in AN. The authors suggest that classic psychedelics, especially psilocybin, may normalize dysfunctional neurobiological systems in AN and offer a novel intervention, particularly for treatment-resistant patients.