The world health organization estimates that there are currently 350 million people suffering from major depressive disorder. This is characterized by dysphoric mood and among the most serious consequences suiciding can became an option, apart from the ...

The current study investigated sex differences in cannabidiol (CBD)-tetrahydrocannabinol (THC) interactions on antinociception and locomotor activity in rats. Experiment 1 tested the hypothesis that CBD enhances THC-induced antinociception on tests of a...

Title: Impact of cannabidiol (CBD) on anxiety symptoms in pediatric epilepsy patients: A preliminary analysisAuthors: Saurav Singh, Breanna Borg, Austin Morales, Julia Evanski, Jamie MacDougall, Amanda Weber, Aimee Luat, Hilary Marusak Funding: The Chil...

Cannabis is the most widely used illicit drug and its chronic use is associated with cannabis use disorder (CUD). THC is an agonist of CB1, and CB2 cannabinoid receptors that are found throughout the brain. The nucleus accumbens shell (NAcs) is importan...

Cannabis is one of the most popular illicit recreational drugs, after alcohol and tobacco. δ9-tetrahydrocannabinol (δ9-THC) is the main psychoactive ingredient in marijuana. It has two stereoisomers, δ9(+) THC and δ9(-) THC, of which the (-) enantiomer ...

Marijuana and its principal psychoactive component, THC, produce characteristic behavioral and physiological effects in humans. However, THC's sites of action in the human brain and their relationships to the drug's actions are not yet well understood. We have previously demonstrated using BOLD fMRI imaging that THC produced dose-related alterations in brain function in several brain regions including nucleus accumbens, amygdala, anterior cingulate, and cerebellum. The purpose of the this study was to determine the relative contributions of neuronal and non-neuronal factors to the observed BOLD signal changes. With that in mind, we examined the effects of THC on cerebral blood flow using arterial spin labeling. Chronic marijuana users were injected iv with THC (0, 0.5, 1, and 3 mg over one-minute in an ethanol vehicle) while undergoing fMRI scanning. A single 8 mm slice containing motor cortex was imaged during rest and motor cortex activation (finger tapping). We found the average flow in the slice at res...

The abuse potential of marijuana in humans is well established but scientific evidence for reinforcing properties of its psychoactive constituent delta-9-tetrahydrocannabinol (THC) in animals is lacking. In the present experiments, high rates of self-administration behavior were consistently maintained in squirrel monkeys by intravenous injections of THC. Mean rates of responding ranged from 0.1 to 0.4 response/sec during daily 1-hr sessions, using a fixed-ratio 10, time-out 60 sec, schedule of i.v. THC injection with doses of 2 to 4 mcg/kg/injection. A second-order, fixed-interval schedule with fixed-ratio components was also studied, in which THC was repeatedly injected only at the end of each daily session in association with a brief visual stimulus (each completion of a fixed-ratio unit during a 30-min fixed interval produced only the brief visual stimulus). Mean rates of responding ranged from 0.06 to 0.2 responses/sec when 10 consecutive injections of 2 to 4 mcg/kg/injection THC spaced 2-sec apart en...

Cannabidiol (CBD) is a non-psychoactive compound derived from the cannabis plant, Cannabis sativa. Previous research has shown CBD’s wide ranging therapeutic effects from antidepressant, antipsychotic, and anti-anxiety studies to preventing social-recog...

E. Downer and V. Campbell. * Dept. of Physiology, Trinity College Dublin, Ireland. Δ9-Tetrahydrocannabinol (THC), the principle psychoactive component of marijuana, elicits diverse psychological effects in humans. At a cellular level THC has been shown to have both neurotoxic1 and neuroprotective effects2. The aim of this study was to examine the role of the stress activated protein kinase (SAPK) c-jun N-terminal kinase (JNK) in THC-induced neurotoxicity in cortical neurones. Treatment of cultured cortical neurones with THC (5µM) for 2h resulted in a 49% increase in genomic DNA strand breaks as assessed by TUNEL staining (p<0.01, paired t-test, n=10). Use of a fluorogenic assay has revealed that caspase-3 activity is increased from 13±6 pmol AFC produced/mg/min (mean±SEM) to 24±8 pmol AFC produced/mg/min following treatment of neurones with THC for 2h. Western Blot analysis showed that cell death was preceded by JNK activation (p<0.05, ANOVA, n=6). The specific role of JNK in this system was assessed by do...

We previously assessed rCBF following smoking of marijuana and placebo as subjects repeatedly performed the same cognitive task. The task provided a stable cognitive baseline but did not allow assessment of direct vs task-related effects of marijuana. The present doubly-blinded study used PET with [O-15]water to measure rCBF in 12 volunteers who smoked marijuana or placebo cigarettes on 2 occasions at least a week apart. On each occasion subjects were imaged after smoking a marijuana (~20 mg THC) or placebo cigarette while performing 3 auditory tasks; a baseline RT task (also presented before smoking), and dichotic listening tasks with attend-right and attend-left ear instructions. As in our previous studies, smoking marijuana resulted in intoxication (self report), increased rCBF in orbital frontal cortex, anterior cingulate, temporal pole, insula, and cerebellum, and reduced rCBF in auditory and visual cortices. These changes occurred in all 3 tasks and appear to be direct effects of marijuana on rCBF. T...