Abstract   Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) are two major constituents of Cannabis sativa. Δ9-THC modulates sleep, but no clear evidence on the role of CBD is available. In order to determine the effects of CBD on sleep, it was administered intracerebroventricular (icv) in a dose of 10 μg/5 μl at the beginning of either the lights-on or the lights-off period. We found that CBD administered during the lights-on period increased wakefulness (W) and decreased rapid eye movement sleep (REMS). No changes on sleep were observed during the dark phase. Icv injections of CBD (10 μg/5 μl) induced an enhancement of c-Fos expression in waking-related brain areas such as hypothalamus...

Background: Oleoylethanolamide (OEA) and palmitoylethanolamide (PEA) are amides of fatty acids and ethanolamine named N-acylethanolamines or acylethanolamides. The hydrolysis of OEA and PEA is catalyzed by the fatty acid amide hydrolase (FAAH). A number of FAAH inhibitors that increase the levels of OEA and PEA in the brain have been developed, including URB597. In the present report, we examined whether URB597, OEA or PEA injected into wake-related brain areas, such as lateral hypothalamus (LH) or dorsal raphe nuclei (DRN) would promote wakefulness (W) in rats. Methodology and Principal Findings: Male Wistar rats (250–300 g) were implanted for sleep studies with electrodes to record the...

Rationale: Cannabis preparations are the most widely consumed illicit drugs, and their use typically begins in adolescence. The prevalence of cannabis abuse is higher in patients with attention deficit/hyperactivity disorder (ADHD) than in the general population, yet, knowledge about the motivational properties of cannabinoids in animal models of ADHD are lacking. Objective: To compare the motivational effects of the synthetic cannabinoid agonist WIN55,212-2 (WIN) in adolescent and adult spontaneously hypertensive rats (SHR), a validated animal model of ADHD, and Wistar rats, representing a “normal” genetically heterogeneous population. We also asked whether the effects of WIN depended (1) on the activation of the cerebral subtype...

Endocannabinoids and their receptors, mainly the CB1 receptor type, function as a retrograde signaling system in many synapses within the CNS, particularly in GABAergic and glutamatergic synapses. They also play a modulatory function on dopamine (DA) transmission, although CB1 receptors do not appear to be located in dopaminergic terminals, at least in the major brain regions receiving dopaminergic innervation, e.g., the caudate-putamen and the nucleus accumbens/prefrontal cortex. Therefore, the effects of cannabinoids on DA transmission and DA-related behaviors are generally indirect and exerted through the modulation of GABA and glutamate inputs received by dopaminergic neurons. Recent evidence suggest, however, that certain eicosanoid-derived cannabinoids may...

The co-occurrence of drug addiction in adults with attention deficit hyperactivity disorder (ADHD) is very common, but its etiology remains largely unknown. Therefore, animal models to study this kind of psychiatric comorbidity are needed. The Spontaneously Hypertensive Rat (SHR) strain shows neurochemical and behavioral characteristics which make it a suitable model of ADHD. Compared with their normotensive controls (Wistar-Kyoto) and with some other rat strains, SHR rats drink more ethanol and are more sensitive to its anxiolytic/stimulant effects. They also show increased sensitivity to psychostimulants, opioids and cannabinoids. Furthermore, chronic treatment with methylphenidate, the first-choice drug to treat ADHD, during adolescence, changes the ethanol...

Over the last decades, the scientific interest in chemistry and pharmacology of cannabinoids has increased. Most attention has focused on Δ9 -tetrahydrocannabinol (Δ9 -THC) as it is the psychoactive constituent of Cannabis sativa (C. sativa). However, in previous years, the focus of interest in the second plant constituent with non-psychotropic properties, cannabidiol (CBD) has been enhanced. Recently, several groups have investigated the pharmacological properties of CBD with significant findings; furthermore, this compound has raised promising pharmacological properties as a wake-inducing drug. In the current review, we will provide experimental evidence regarding the potential role of CBD as a wake-inducing drug.