CB1 receptor antagonism blocks stress-potentiated reinstatement of cocaine seeking in rats.

“Under some conditions, stress, rather than directly triggering cocaine seeking, potentiates reinstatement to other stimuli, including a subthreshold cocaine dose.

Endocannabinoid signaling is increased by stress and regulates synaptic transmission in brain regions implicated in motivated behavior.

The objective of this study was to test the hypothesis that cannabinoid type 1 receptor (CB1R) signaling is required for stress-potentiated reinstatement of cocaine seeking in rats…

These findings demonstrate that footshock stress increases prefrontal cortical endocannabinoids and stress-potentiated reinstatement is CB1R-dependent, suggesting that CB1R is a potential therapeutic target for relapse prevention, particularly in individuals whose cocaine use is stress-related.”

http://www.ncbi.nlm.nih.gov/pubmed/26455361

The effects of endocannabinoid receptor agonist anandamide and antagonist rimonabant on opioid analgesia and tolerance in rats.

“The role of the cannabinoid (CB) system in the tolerance to analgesic effect of opioid remains obscure. The aim of the present study was to evaluate the effects of the endocannabinoid nonselective receptor agonist anandamide (AEA) and CB1 receptor antagonist rimonabant (SR141716) on morphine analgesia and tolerance in rats.

The findings suggested that AEA in combination with morphine produced a significant increase in expression of analgesic tolerance to morphine.

Conversely, cannabinoid receptor antagonist SR141716 attenuated morphine analgesic tolerance.

In addition, administration of AEA with morphine increased morphine analgesia.

In conclusion, we observed that the cannabinoid receptor agonist anandamide and CB1 receptor antagonist SR141716 plays a significant role in the opioid analgesia and tolerance.”

http://www.ncbi.nlm.nih.gov/pubmed/26374993

Cannabis as a substitute for alcohol and other drugs.

Logo of harmred

“This study examined drug and alcohol use, and the occurrence of substitution among medical cannabis patients.

The substitution of one psychoactive substance for another with the goal of reducing negative outcomes can be included within the framework of harm reduction.

Medical cannabis patients have been engaging in substitution by using cannabis as an alternative to alcohol, prescription and illicit drugs.”

http://www.ncbi.nlm.nih.gov/pubmed/19958538

“The substitution of one psychoactive substance for another with the goal of reducing negative outcomes can be included within the framework of harm reduction. Medical cannabis patients have been engaging in substitution by using cannabis as an alternative to alcohol, prescription and illicit drugs.

This brings up two important points. First, self determination, the right of an individual to decide which treatment or substance is most effective and least harmful for them. If an individual finds less harm in cannabis than in the drug prescribed by their doctor, do they have a right to choose? Secondly, the recognition that substitution might be a viable alternative to abstinence for those who are not able, or do not wish to stop using psychoactive substances completely.” http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2795734/

Substituting cannabis for prescription drugs, alcohol and other substances among medical cannabis patients: The impact of contextual factors.

“The present study examines the use of cannabis as a substitute for alcohol, illicit substances and prescription drugs among 473 adults who use cannabis for therapeutic purposes.

Substituting cannabis for one or more of alcohol, illicit drugs or prescription drugs was reported by 87% of respondents, with 80.3% reporting substitution for prescription drugs, 51.7% for alcohol, and 32.6% for illicit substances.

Respondents who reported substituting cannabis for prescription drugs were more likely to report difficulty affording sufficient quantities of cannabis, and patients under 40 years of age were more likely to substitute cannabis for all three classes of substance than older patients.

The finding that cannabis was substituted for all three classes of substances suggests that the medical use of cannabis may play a harm reduction role in the context of use of these substances,”

http://www.ncbi.nlm.nih.gov/pubmed/26364922

Cannabinoid Ligands and Alcohol Addiction: A Promising Therapeutic Tool or a Humbug?

“The vast therapeutic potential of cannabinoids of both synthetic and plant-derived origins currently makes these compounds the focus of a growing interest. Although cannabinoids are still illicit drugs, their possible clinical usefulness, including treatment of acute or neuropathic pain, have been suggested by several studies.

In addition, some observations indicate that cannabinoid receptor antagonists may be useful for the treatment of alcohol dependence and addiction, which is a major health concern worldwide.

While the synergism between alcohol and cannabinoid agonists (in various forms) creates undesirable side effects when the two are consumed together, the administration of CB1 antagonists leads to a significant reduction in alcohol consumption.

Furthermore, cannabinoid antagonists also mitigate alcohol withdrawal symptoms.

Herein, we present an overview of studies focusing on the effects of cannabinoid ligands (agonists and antagonists) during acute or chronic consumption of ethanol.”

http://www.ncbi.nlm.nih.gov/pubmed/26353844

Pregnenolone can protect the brain from cannabis intoxication.

“Pregnenolone is considered the inactive precursor of all steroid hormones, and its potential functional effects have been largely uninvestigated.

The administration of the main active principle of Cannabis sativa (marijuana), Δ(9)-tetrahydrocannabinol (THC), substantially increases the synthesis of pregnenolone in the brain via activation of the type-1 cannabinoid (CB1) receptor.

Pregnenolone then, acting as a signaling-specific inhibitor of the CB1 receptor, reduces several effects of THC.

This negative feedback mediated by pregnenolone reveals a previously unknown paracrine/autocrine loop protecting the brain from CB1 receptor overactivation that could open an unforeseen approach for the treatment of cannabis intoxication and addiction.

These data indicate that THC increases pregnenolone through activation of the CB1 receptor…

In conclusion, this new understanding of the role of pregnenolone has the potential to generate new therapies for cannabis dependence.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4057431/

Enhancing Brain Pregnenolone May Protect Cannabis Intoxication but Should Not Be Considered as an Anti-addiction Therapeutic: Hypothesizing Dopaminergic Blockade and Promoting Anti-Reward.

“Pregnenolone considered the inactive precursor of all steroid hormones, has recently been shown to protect the brain from Cannabis intoxication.

The major active ingredient of Cannabis sativa (marijuana), Δ9-tetrahydrocannabinol (THC) enhances Pregnenolone synthesis in the brain via stimulation of the type-1 cannabinoid (CB1) receptor.

This steroid has been shown to inhibit the activity of the CB1 receptor thereby reducing many of the effects of THC.

While this mechanism seems correct, in our opinion, Vallee et al., incorrectly suggest that blocking CB1 receptors could open unforeseen approaches to the treatment of cannabis intoxication and addiction.

In this hypothesis, we caution the scientific community that, other CB1 receptor blockers, such as, Rimonabant (SR141718) have been pulled off the market in Europe. In addition, CB1 receptor blockers were rejected by the FDA due to mood changes including suicide ideation.

Blocking CB1 receptors would result in reduced neuronal release of Dopamine by disinhibition of GABA signaling.

Long-term blockade of cannabinoid receptors could occur with raising Pregnenolone brain levels…”

http://www.ncbi.nlm.nih.gov/pubmed/26306328

Cannabidiol, a Cannabis sativa constituent, inhibits cocaine-induced seizures in mice: Possible role of the mTOR pathway and reduction in glutamate release.

“Cannabidiol (CBD), a major non-psychotomimetic constituent of Cannabis sativa, has therapeutic potential for certain psychiatric and neurological disorders.

Studies in laboratory animals and limited human trials indicate that CBD has anticonvulsant and neuroprotective properties.

Its effects against cocaine neurotoxicity, however, has remained unclear. Thus, the present study tested the hypothesis that CBD protects against cocaine-induced seizures and investigated the underlying mechanisms.

In conclusion, CBD protects against seizures in a model of cocaine intoxication.

CBD should be further investigated as a strategy for alleviating psychostimulant toxicity.”

http://www.ncbi.nlm.nih.gov/pubmed/26283212

Early Phase in the Development of Cannabidiol as a Treatment for Addiction: Opioid Relapse Takes Initial Center Stage.

“Multiple cannabinoids derived from the marijuana plant have potential therapeutic benefits but most have not been well investigated, despite the widespread legalization of medical marijuana in the USA and other countries.

Therapeutic indications will depend on determinations as to which of the multiple cannabinoids, and other biologically active chemicals that are present in the marijuana plant, can be developed to treat specific symptoms and/or diseases.

Such insights are particularly critical for addiction disorders, where different phytocannabinoids appear to induce opposing actions that can confound the development of treatment interventions. Whereas Δ9-tetracannabinol has been well documented to be rewarding and to enhance sensitivity to other drugs, cannabidiol (CBD), in contrast, appears to have low reinforcing properties with limited abuse potential and to inhibit drug-seeking behavior.

Other considerations such as CBD’s anxiolytic properties and minimal adverse side effects also support its potential viability as a treatment option for a variety of symptoms associated with drug addiction.

However, significant research is still needed as CBD investigations published to date primarily relate to its effects on opioid drugs, and CBD’s efficacy at different phases of the abuse cycle for different classes of addictive substances remain largely understudied.

Our paper provides an overview of preclinical animal and human clinical investigations, and presents preliminary clinical data that collectively sets a strong foundation in support of the further exploration of CBD as a therapeutic intervention against opioid relapse.

As the legal landscape for medical marijuana unfolds, it is important to distinguish it from “medical CBD” and other specific cannabinoids, that can more appropriately be used to maximize the medicinal potential of the marijuana plant.”

http://www.ncbi.nlm.nih.gov/pubmed/26269227

The effects of dronabinol during detoxification and the initiation of treatment with extended release naltrexone.

“Evidence suggests that the cannabinoid system is involved in the maintenance of opioid dependence. We examined whether dronabinol, a cannabinoid receptor type 1 partial agonist, reduces opioid withdrawal and increases retention in treatment with extended release naltrexone (XR-naltrexone).

CONCLUSION:

Dronabinol reduced the severity of opiate withdrawal during acute detoxification but had no effect on rates of XR-naltrexone treatment induction and retention. Participants who elected to smoke marijuana during the trial were more likely to complete treatment regardless of treatment group assignment.”

http://www.ncbi.nlm.nih.gov/pubmed/26187456