Abstract Acutely, 3,4,‐methylenedioxymethamphetamine (MDMA) induces cerebrovascular dysfunction [ Quate et al ., (2004) Psychopharmacol. , 173 , 287–295]. In the longer term the same single dose results in depletion of 5‐hydroxytrptamine (5‐HT) nerve terminals. In this study we examined the cerebrovascular consequences of this persistent neurodegeneration, and the acute effects of subsequent...
Abstract Chronic l ‐3,4‐dihydroxyphenylalanine (L‐DOPA) pharmacotherapy in Parkinson's disease is often accompanied by the development of abnormal and excessive movements known as dyskinesia. Clinical and experimental studies indicate that indirect serotonin agonists can suppress dyskinesia without affecting the efficacy of L‐DOPA. While the mechanism by which these effects occur is not clear,...
The noradrenergic pathway arising from the locus coeruleus (LC) is involved in the regulation of attention, arousal, cognitive processes and sleep. These physiological activities are affected by Cannabis exposure - both in humans and laboratory animals. In addition, exogenous cannabinoids, as well as pharmacological and genetic manipulation of the endocannabinoid system, are known to influence...
A2A adenosine and CB1 cannabinoid receptors are highly expressed in the central nervous system, where they modulate numerous physiological processes including adaptive responses to drugs of abuse. Both purinergic and cannabinoid systems interact with dopamine neurotransmission (through A2A and CB1 receptors, respectively). Changes in dopamine neurotransmission play an important role in...
Adult male Long-Evans rats were administered the potent cannabinoid 1 receptor agonist HU-210 (100 microg/kg, i.p.) for 15 days continuously and their performance on a matching-to-place version of the Morris water maze was subsequently evaluated. Overall, experimental animals performed significantly worse initially on the reference memory component of this task, but their performance improved...
Abstract The involvement of µ‐opioid receptors in the rewarding properties of MDMA was explored in µ‐opioid receptor knockout mice using the conditioning place preference paradigm. The associated release of dopamine in the nucleus accumbens was investigated by in vivo microdialysis. A significant rewarding effect of MDMA (10 mg/kg, i.p.) was observed in both wild‐type and µ‐opioid receptor...
Abstract Drugs of abuse, such as 3,4‐methylenedioxymethamphetamine (MDMA), often have more powerful effects during states of increased activation and under specific environmental conditions. Because hyperthermia is a major complication of MDMA use and a factor potentiating neurotoxicity, we examined the effects of this drug (9 mg/kg, sc; approximately one‐fifth of the known LD 50 in rats) on...
The effect of prior exposure to methylenedioxyamphetamine (MDA) on behavioural and neurochemical responses to fluoxetine were assessed in a rat model of antidepressant action. MDA (7.5 mg/kg, i.p.) was administered to rats twice daily for 4 consecutive days, and 4 weeks later the behavioural effect of fluoxetine (5 or 20 mg/kg; i.p. x 3) was examined in the modified rat forced-swimming test. In...
The commonsense view of religious experience is that it is a preconceptual, immediate affective event. Work in philosophy and psychology, however, suggest that religious experience is an attributional cognitive phenomenon. Here the neural correlates of a religious experience are investigated using functional neuroimaging. During religious recitation, self-identified religious subjects activated...
This study investigated whether the nitric oxide pathway was involved in the central effects of Delta(9)-tetrahydrocannabinol (Delta(9)-THC), the major psychoactive constituent of cannabis sativa. Body temperature, nociception and locomotion were measured in neuronal nitric oxide synthase (nNOS) knock-out (KO) mice and wild-type (WT) controls after intraperitoneal application of Delta(9)-THC....
Abstract The pharmacological basis of acute (±)‐MDMA (3,4‐methylenedioxymethamphetamine) intoxication still awaits full characterization. According to present knowledge, MDMA enhances the release of serotonin and dopamine in striatal slices and interacts with different types of receptors such as 5‐HT 2 (5‐hydroxytryptamine or serotonin), M 1 and M 2 muscarinic acetylcholine (ACh), and histamine...
Abstract Both the phenethylamine hallucinogen (–)‐1‐2,5‐dimethoxy‐4‐bromophenyl‐2‐aminopropane (DOB), a selective serotonin 5‐HT 2A,2C receptor agonist, and the indoleamine hallucinogen d ‐lysergic acid diethylamide (LSD, which binds to 5‐HT1A, 1B, 1D, 1E, 1F, 2A, 2C, 5, 6, 7, dopamine D 1 and D 2 , and α 1 and α 2 adrenergic receptors), but not their non‐hallucinogenic congeners, inhibited...
We have studied in the rat the effects of acute subcutaneous injection of psychotomimetics including methamphetamine (MAP), cocaine and phencyclidine (PCP) on the expression of a brain plasticity-related molecule, tissue plasminogen activator (tPA) mRNA, using non-radioactive in situ hybridization histochemistry. In addition to the constitutive expression of tPA mRNA in cerebellar Purkinje...