European Neuropsychopharmacology
July 2014
Serena Stopponi, Laura Soverchia, Massimo Ubaldi et al.
Cannabis derivatives are among the most widely used illicit substances among young people. The addictive potential of delta-9-tetrahydrocannabinol (THC), the major active ingredient of cannabis is well documented in scientific literature. However, the consequence of THC exposure during adolescence on occurrence of addiction for other drugs of abuse later in life is still controversial. To...
International Journal of Methods in Psychiatric Research
June 2014
Daniel Kleinloog, Frits Roozen, Willem De Winter et al.
The subjective effects of cannabis and its main psychoactive component Δ(9) -tetrahydrocannabinol (THC) have played an important part in determining the therapeutic potential of cannabinoid agonists and antagonists. The effects mainly consist of feeling high, changes in perception, feelings of relaxation and occasionally dysphoric reactions. These effects are captured by two of the most...
Behavioural Pharmacology
June 2014
William S Hyatt, William E Fantegrossi
The emergence of high-efficacy synthetic cannabinoids as drugs of abuse in readily available K2/'Spice' smoking blends has exposed users to much more potent and effective substances than the phytocannabinoids present in cannabis. Increasing reports of adverse reactions, including dependence and withdrawal, are appearing in the clinical literature. Here we investigated whether the effects of one...
Psychopharmacology
June 2014
Mohini Ranganathan, R Andrew Sewell, Michelle Carbuto et al.
A family history (FH) of alcoholism accounts for approximately 50% of the risk of developing alcohol problems. Several lines of preclinical evidence suggest that brain cannabinoid receptor (CB1R) function may mediate the effects of alcohol and risk for developing alcoholism including the observations that reduced CB1R function decreases alcohol-related behaviors and enhanced CB1R function...
Frontiers in Psychiatry
May 22, 2014
Rajiv Radhakrishnan, Samuel T. Wilkinson, Deepak Cyril Dâ€TMSouza
312 citations
Cannabis is the most commonly used illicit drug worldwide, with ~5 million daily users worldwide. Emerging evidence supports a number of associations between cannabis and psychosis/psychotic disorders, including schizophrenia. These associations-based on case-studies, surveys, epidemiological studies, and experimental studies indicate that cannabinoids can produce acute, transient effects;...
Current Pharmaceutical Design
May 10, 2014
Johannes Wrege, André Schmidt, Anna Walter et al.
96 citations
We conducted a systematic review to assess the evidence for specific effects of cannabis on impulsivity, disinhibition and motor control. The review had a specific focus on neuroimaging findings associated with acute and chronic use of the drug and covers literature published up until May 2012. Seventeen studies were identified, of which 13 met the inclusion criteria; three studies investigated...
Neuropsychopharmacology
May 2014
Henrietta Szutorisz, Jennifer A DiNieri, Eric Sweet et al.
Recent attention has been focused on the long-term impact of cannabis exposure, for which experimental animal studies have validated causal relationships between neurobiological and behavioral alterations during the individual's lifetime. Here, we show that adolescent exposure to Δ(9)-tetrahydrocannabinol (THC), the main psychoactive component of cannabis, results in behavioral and...
Journal of Neuroscience
April 16, 2014
Jodi M Gilman, John K Kuster, Sang H. Lee et al.
Marijuana is the most commonly used illicit drug in the United States, but little is known about its effects on the human brain, particularly on reward/aversion regions implicated in addiction, such as the nucleus accumbens and amygdala. Animal studies show structural changes in brain regions such as the nucleus accumbens after exposure to Δ9-tetrahydrocannabinol, but less is known about...
Journal of Neuroscience
April 9, 2014
Daniel J Morgan, Brian J Davis, Chris S Kearn et al.
For many G-protein-coupled receptors (GPCRs), including cannabinoid receptor 1 (CB1R), desensitization has been proposed as a principal mechanism driving initial tolerance to agonists. GPCR desensitization typically requires phosphorylation by a G-protein-coupled receptor kinase (GRK) and interaction of the phosphorylated receptor with an arrestin. In simple model systems, CB1R is desensitized...
Journal of Psychiatric Research
April 2014
Jesus Pujol, Laura Blanco‐Hinojo, Albert Batalla et al.
Recreational drugs are generally used to intentionally alter conscious experience. Long-lasting cannabis users frequently seek this effect as a means to relieve negative affect states. As with conventional anxiolytic drugs, however, changes in subjective feelings may be associated with memory impairment. We have tested whether the use of cannabis, as a psychoactive compound, is associated with...
The EMBO journal
April 1, 2014
Giuseppe Tortoriello, Claudia V Morris, Alán Alpár et al.
Children exposed in utero to cannabis present permanent neurobehavioral and cognitive impairments. Psychoactive constituents from Cannabis spp., particularly Δ(9)-tetrahydrocannabinol (THC), bind to cannabinoid receptors in the fetal brain. However, it is unknown whether THC can trigger a cannabinoid receptor-driven molecular cascade to disrupt neuronal specification. Here, we show that...
Psychopharmacology
April 2014
Reagan R Wetherill, Anna Rose Childress, Kanchana Jagannathan et al.
Addiction theories posit that drug-related cues maintain and contribute to drug use and relapse. Indeed, our recent study in cocaine-dependent patients demonstrated that subliminally presented cocaine-related stimuli activate reward neurocircuitry without being consciously perceived. Activation of reward neurocircuitry may provoke craving and perhaps prime an individual for subsequent...
American Journal of Psychiatry
April 2014
Christopher D. Verrico, Hong Gu, Melanie L Peterson et al.
Epidemiological findings suggest that, relative to adults, adolescents are more vulnerable to the adverse persistent effects of cannabis on working memory. However, the potential confounds inherent in human studies preclude direct determination of a cause-and-effect relationship between adolescent cannabis use and heightened susceptibility to persistent working memory impairments. Consequently,...
Neurobiology of Disease
March 1, 2014
Erica Zamberletti, Sarah Beggiato, Luca Steardo et al.
Although several findings indicate an association between adolescent cannabis abuse and the risk to develop schizophrenia later in life, the evidence for a causal relationship is still inconclusive. In the present study, we investigated the emergence of psychotic-like behavior in adult female rats chronically exposed to delta-9-tetrahydrocannabinol (THC) during adolescence. To this aim, female...
Brain Research
February 22, 2014
Ryan W J Steel, John H Miller, Dalice A Sim et al.
Cannabis is the most widely used illicit drug, and disruption of learning and memory are commonly reported consequences of cannabis use. We have previously demonstrated a spatial learning impairment by ∆(9)-tetrahydrocannabinol (THC) in adolescent Sprague-Dawley rats (Steel et al., 2011). The molecular mechanisms underlying behavioural impairment by cannabis remain poorly understood, although...
Addictive Behaviors
February 6, 2014
A. Thames, Natalie Arbid, Philip Sayegh
Objective With the recent debates over marijuana legalization and increases in use, it is critical to examine its role in cognition. While many studies generally support the adverse acute effects of cannabis on neurocognition, the non-acute effects remain less clear. The current study used a cross-sectional design to examine relationships between recent and past cannabis use on neurocognitive...
Pharmacology, Biochemistry, and Behavior
February 2014
Peter J Winsauer, Jessie L Sutton
This study examined whether chronic Δ(9)-THC during early adulthood would produce the same hormonally-dependent deficits in learning that are produced by chronic Δ(9)-THC during adolescence. To do this, either sham-operated (intact) or ovariectomized (OVX) female rats received daily saline or 5.6 mg/kg of Δ(9)-THC i.p. for 40 days during early adulthood. Following chronic administration, and a...
International Journal of Drug Policy
January 2014
Ian Hamilton, Charlie Lloyd, Catherine Hewitt et al.
The UK Misuse of Drugs Act (1971) divided controlled drugs into three groups A, B and C, with descending criminal sanctions attached to each class. Cannabis was originally assigned by the Act to Group B but in 2004, it was transferred to the lowest risk group, Group C. Then in 2009, on the basis of increasing concerns about a link between high strength cannabis and schizophrenia, it was moved...
Current Pharmaceutical Design
2014
Joanna Jacobus, Susan F Tapert
This article reviews neuroimaging, neurocognitive, and preclinical findings on the effects of cannabis on the adolescent brain. Marijuana is the second most widely used intoxicant in adolescence, and teens who engage in heavy marijuana use often show disadvantages in neurocognitive performance, macrostructural and microstructural brain development, and alterations in brain functioning. It...
Current Pharmaceutical Design
2014
Albert Batalla, José A. Crippa, Geraldo F. Busatto et al.
In recent years, growing concerns about the effects of cannabis use on mental health have renewed interest in cannabis research. In particular, there has been a marked increase in the number of neuroimaging studies of the effects of cannabinoids. We conducted a systematic review to assess the impact of acute cannabis exposure on brain function in humans and in experimental animals. Papers...