Tag Archives: cannabinoid

Possible mechanisms of cannabinoid-induced antinociception in the spinal cord.

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European Journal of Pharmacology

“Anandamide is an endogenous ligand at both the inhibitory cannabinoid CB(1) receptor and the excitatory vanilloid receptor 1 (VR1). The CB(1) receptor and vanilloid VR1 receptor are expressed in about 50% and 40% of dorsal root ganglion neurons, respectively. While all vanilloid VR1 receptor-expressing cells belong to the calcitonin gene-related peptide-containing and isolectin B4-binding sub-populations of nociceptive primary sensory neurons, about 80% of the cannabinoid CB(1) receptor-expressing cells belong to those sub-populations. Furthermore, all vanilloid VR1 receptor-expressing cells co-express the cannabinoid CB(1) receptor.

In agreement with these findings, neonatal capsaicin treatment that induces degeneration of capsaicin-sensitive, vanilloid VR1 receptor-expressing, thin, unmyelinated, nociceptive primary afferent fibres significantly reduced the cannabinoid CB(1) receptor immunostaining in the superficial spinal dorsal horn.

Synthetic cannabinoid CB(1) receptor agonists, which do not have affinity at the vanilloid VR1 receptor, and low concentrations of anandamide both reduce the frequency of miniature excitatory postsynaptic currents and electrical stimulation-evoked or capsaicin-induced excitatory postsynaptic currents in substantia gelatinosa cells in the spinal cord without any effect on their amplitude. These effects are blocked by selective cannabinoid CB(1) receptor antagonists. Furthermore, the paired-pulse ratio is increased while the postsynaptic response of substantia gelatinosa neurons induced by alpha-amino-3-hydroxy-5-methylisoxasole-propionic acid (AMPA) in the presence of tetrodotoxin is unchanged following cannabinoid CB(1) receptor activation.

These results strongly suggest that the cannabinoid CB(1) receptor is expressed presynaptically and that the activation of these receptors by synthetic cannabinoid CB(1) receptor agonists or low concentration of anandamide results in inhibition of transmitter release from nociceptive primary sensory neurons. High concentrations of anandamide, on the other hand, increase the frequency of miniature excitatory postsynaptic currents recorded from substantia gelatinosa neurons. This increase is blocked by ruthenium red, suggesting that this effect is mediated through the vanilloid VR1 receptor.

Thus, anandamide at high concentrations can activate the VR1 and produce an opposite, excitatory effect to its inhibitory action produced at low concentrations through cannabinoid CB(1) receptor activation. This “dual”, concentration-dependent effect of anandamide could be an important presynaptic modulatory mechanism in the spinal nociceptive system.”

https://www.ncbi.nlm.nih.gov/pubmed/11698030

https://www.sciencedirect.com/science/article/pii/S0014299901013097?via%3Dihub

The nonpsychotropic cannabinoid cannabidiol modulates and directly activates alpha-1 and alpha-1-Beta glycine receptor function.

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“Loss of inhibitory synaptic transmission within the dorsal horn of the spinal cord plays a key role in the development of chronic pain following inflammation or nerve injury. Inhibitory postsynaptic transmission in the adult spinal cord involves mainly glycine.

Cannabidiol is a nonpsychotropic plant constituent of Cannabis sativa.

As we hypothesized that non-CB receptor mechanisms of cannabidiol might contribute to its anti-inflammatory and neuroprotective effects, we investigated the interaction of cannabidiol with strychnine-sensitive alpha(1 )and alpha(1)beta glycine receptors by using the whole-cell patch clamp technique.

Cannabidiol showed a positive allosteric modulating effect in a low micromolar concentration range (EC(50) values: alpha(1) = 12.3 +/- 3.8 micromol/l and alpha(1)beta = 18.1 +/- 6.2 micromol/l). Direct activation of glycine receptors was observed at higher concentrations above 100 micromol/l (EC(50) values: alpha(1) = 132.4 +/- 12.3 micromol/l and alpha(1)beta = 144.3 +/- 22.7 micromol/l).

These in vitro results suggest that strychnine-sensitive glycine receptors may be a target for cannabidiol mediating some of its anti-inflammatory and neuroprotective properties.”

https://www.ncbi.nlm.nih.gov/pubmed/19204413

https://www.karger.com/Article/Abstract/201556

Cannabinoids and gastrointestinal motility: Pharmacology, clinical effects, and potential therapeutics in humans.

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“Cannabinoid agents and cannabis are frequently used for relief of diverse gastrointestinal symptoms.

PURPOSE:

The objective of this article is to increase the awareness of gastroenterologists to the effects of cannabinoids on gastrointestinal motility, as gastroenterologists are likely to encounter patients who are taking cannabinoids, or those with dysmotility that may be associated with cannabinoid mechanisms.

The non-selective cannabinoid agonist, dronabinol, retards gastric emptying and inhibits colonic tone and phasic pressure activity.

In summary, cannabinoid mechanisms and pharmacology are relevant to the current and future practice of clinical gastroenterology.”

https://www.ncbi.nlm.nih.gov/pubmed/29745439

https://onlinelibrary.wiley.com/doi/abs/10.1111/nmo.13370

Marijuana Use Is Not Associated With Progression to Advanced Liver Fibrosis in HIV/Hepatitis C Virus-coinfected Women.

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“Marijuana (hereafter “tetrahydrocannabinol [THC]”) use has been associated with liver fibrosis progression in retrospective analyses of patients with chronic hepatitis C (HCV). We studied long-term effects of THC on fibrosis progression in women coinfected with human immunodeficiency virus (HIV)/HCV enrolled in the Women’s Interagency HIV Study (WIHS).

CONCLUSIONS:

In this large cohort of HIV/HCV-coinfected women, THC was not associated with progression to significant liver fibrosis. Alcohol use was independently associated with liver fibrosis, and may better predict fibrosis progression in HIV/HCV-coinfected women.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4967608/

https://academic.oup.com/cid/article/63/4/512/2595097

LH-21, A Peripheral Cannabinoid Receptor 1 Antagonist, Exerts Favorable Metabolic Modulation Including Antihypertensive Effect in KKAy Mice by Regulating Inflammatory Cytokines and Adipokines on Adipose Tissue.

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“Patients with obesity are susceptible to hypertension and diabetes. Over-activation of cannabinoid receptor 1 (CB1R) in adipose tissue is proposed in the pathophysiology of metabolic disorders, which led to the metabolic dysfunction of adipose tissue and deregulated production and secretion of adipokines.

In the current study, we determined the impact of LH-21, a representative peripheral CB1R antagonist, on the obesity-accompanied hypertension and explored the modulatory action of LH-21 on the adipose tissue in genetically obese and diabetic KKAy mice.

3-week LH-21 treatment significantly decreased blood pressure with a concomitant reduction in body weight, white adipose tissue (WAT) mass, and a slight loss on food intake in KKAy mice. Meanwhile, glucose handling and dyslipidemia were also markedly ameliorated after treatment. Gene expression of pro-inflammatory cytokines in WAT and the aortae were both attenuated apparently by LH-21, as well the mRNA expression of adipokines (lipocalin-2, leptin) in WAT. Concomitant amelioration on the accumulation of lipocalin-2 was observed in both WAT and aortae. In corresponding with this, serum inflammatory related cytokines (tumor necrosis factor α, IL-6, and CXCL1), and lipocalin-2 and leptin were lowered notably.

Thus according to current results, it can be concluded that the peripheral CB1R antagonist LH-21 is effective in managing the obesity-accompanied hypertension in KKAy mice. These metabolic benefits are closely associated with the regulation on the production and secretion of inflammatory cytokines and adipokines in the WAT, particularly alleviated circulating lipocalin-2 and its accumulation in aortae.”

https://www.ncbi.nlm.nih.gov/pubmed/29731737

https://www.frontiersin.org/articles/10.3389/fendo.2018.00167/full

The Impact of Δ9-THC on the Psychological Symptoms of Anorexia Nervosa: A Pilot Study.

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“Δ9-Tetrahydrocannabinol (Δ9-THC) is the active compound of Cannabis sativa with appetite stimulating properties.

This study evaluated the effect of low doses of oral Δ9-THC on self-reported symptoms of patients suffering from chronic anorexia nervosa (AN).

The primary outcome was improvement in the way patients perceived their eating behavior.

Significant improvements were found in self reported body care, sense of ineffectiveness, asceticism and depression. There were no significant changes in BMI.

Δ9-THC may be an effective component in treating the psychological symptoms of AN.”

https://www.ncbi.nlm.nih.gov/pubmed/29735812

Cannabinoid-Opioid Interaction in Chronic Pain

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“Cannabis inhalation with a vaporizer may enhance the analgesia of opioids.

In addition, previous research suggest that Cannabis may be useful in attenuating the development of opioid tolerance and dependence.

This is the first human study to show that inhaled cannabis safely potentiates the analgesia of opioids.

HUMAN STUDY SHOWS INHALED CANNABIS POTENTIATES ANALGESIA OF OPIOIDS.”

https://www.naturalmedicinejournal.com/journal/2012-06/cannabinoid-opioid-interaction-chronic-pain

Antinociceptive Synergy between 9 -Tetrahydrocannabinol and Opioids after Oral Administration

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“Cannabinoids and opioids have been shown to possess several similar pharmacological effects, including analgesia

The analgesic effects of opioids, such as morphine and codeine, in mice are enhanced by oral administration of the cannabinoid 9 -tetrahydrocannabinol (9 -THC).

These findings suggest that the use of a low-dose combination of analgesics is a valid and effective approach for the treatment of pain and necessitates further study.

In summary, we have observed that 9 -THC enhances the antinociceptive effects of morphine and codeine in a synergistic fashion. This is the first report of a true synergistic interaction between oral 9 -THC and morphine or codeine, since previous studies have only examined one-dose combinations.

Much more work needs to be done to elucidate the mechanisms by which cannabinoids and opioids interact to produce analgesia. However, the implication that a combination of drugs may be more effective than either drug alone, and at the same time possibly reduce the occurrence of side effects, should provoke further study on analgesic drug interactions.”

http://jpet.aspetjournals.org/content/jpet/304/3/1010.full.pdf

http://healthdocbox.com/Substance_Abuse/71109245-Antinociceptive-synergy-between-9-tetrahydrocannabinol-and-opioids-after-oral-administration.html

Molecular and cellular basis of cannabinoid and opioid interactions.

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 Pharmacology Biochemistry and Behavior

“Cannabinoids and opioids have been shown to possess several similar pharmacological effects, including analgesia and stimulation of brain circuitry that are believed to underlie drug addiction and reward. In recent years, these phenomena have supported the possible existence of functional links in the mechanisms of action of both types of drugs.

The present review addresses the recent advances in the study of biochemical and molecular mechanisms underlying opioid and cannabinoid interaction. Several hypothesis have been formulated to explain this cross-modulation including the release of opioid peptides by cannabinoids or endocannabinoids by opioids and interaction at the level of receptor and/or their signal transduction mechanisms.

Moreover it is important to consider that the nature of cannabinoid and opioid interaction might differ in the brain circuits mediating reward and in those mediating other pharmacological properties, such as antinociception.

Further studies are needed since a better knowledge of the opioid-cannabinoid interaction may lead to exciting therapeutic possibilities.”

https://www.ncbi.nlm.nih.gov/pubmed/15927245

https://www.sciencedirect.com/science/article/pii/S0091305705001450?via%3Dihub

Opioids and cannabinoids interactions: involvement in pain management.

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“Among several pharmacological properties, analgesia is the most common feature shared by either opioid or cannabinoid systems.

Cannabinoids and opioids are distinct drug classes that have been historically used separately or in combination to treat different pain states.

Indeed, it is widely known that activation of either opioid or cannabinoid systems produce antinociceptive properties in different pain models.

Moreover, several biochemical, molecular and pharmacological studies support the existence of reciprocal interactions between both systems, suggesting a common underlying mechanism.

Further studies have demonstrated that the endogenous opioid system could be involved in cannabinoid antinociception and recent data have also provided evidence for a role of the endogenous cannabinoid system in opioid antinociception.

These interactions may lead to additive or even synergistic antinociceptive effects, emphasizing their clinical relevance in humans in order to enhance analgesic effects with lower doses and consequently fewer undesirable side effects.

Thus, the present review is focused on bidirectional interactions between opioids and cannabinoids and their potent repercussions on pain modulation.”

https://www.ncbi.nlm.nih.gov/pubmed/20017728

http://www.eurekaselect.com/71318/article