“Patients have reliably endorsed the belief that cannabis is helpful in alleviating pain. Cannabinoids (the collective term for all of the drugs examined in this study, including plant-based cannabis, which can contain multiple compounds) have long been considered effective for reducing pain and are frequently proposed as treatment options in pain management. Cannabinoid drugs may prevent the onset of pain by producing small increases in pain thresholds but may not reduce the intensity of experimental pain already being experienced; instead, cannabinoids may make experimental pain feel less unpleasant and more tolerable, suggesting an influence on affective processes. Cannabis-induced improvements in pain-related negative affect may underlie the widely held belief that cannabis relieves pain.”
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Effect of cannabidiolic acid and ∆9-tetrahydrocannabinol on carrageenan-induced hyperalgesia and edema in a rodent model of inflammatory pain.
“Cannabidiol (CBD), a non-intoxicating component of cannabis, or the psychoactive Δ9-tetrahydrocannabiol (THC), shows anti-hyperalgesia and anti-inflammatory properties.
OBJECTIVES:
The present study evaluates the anti-inflammatory and anti-hyperalgesia effects of CBD’s potent acidic precursor, cannabidiolic acid (CBDA), in a rodent model of carrageenan-induced acute inflammation in the rat hind paw, when administered systemically (intraperitoneal, i.p.) or orally before and/or after carrageenan. In addition, we assess the effects of oral administration of THC or CBDA, their mechanism of action, and the efficacy of combined ineffective doses of THC and CBDA in this model. Finally, we compare the efficacy of CBD and CBDA.RESULTS:
CBDA given i.p. 60 min prior to carrageenan (but not 60 min after carrageenan) produced dose-dependent anti-hyperalgesia and anti-inflammatory effects. In addition, THC or CBDA given by oral gavage 60 min prior to carrageenan produced anti-hyperalgesia effects, and THC reduced inflammation. The anti-hyperalgesia effects of THC were blocked by SR141716 (a cannabinoid 1 receptor antagonist), while CBDA’s effects were blocked by AMG9810 (a transient receptor potential cation channel subfamily V member 1 antagonist). In comparison to CBDA, an equivalent low dose of CBD did not reduce hyperalgesia, suggesting that CBDA is more potent than CBD for this indication. Interestingly, when ineffective doses of CBDA or THC alone were combined, this combination produced an anti-hyperalgesia effect and reduced inflammation.CONCLUSION:
CBDA or THC alone, as well as very low doses of combined CBDA and THC, has anti-inflammatory and anti-hyperalgesia effects in this animal model of acute inflammation.” https://www.ncbi.nlm.nih.gov/pubmed/30225659 https://link.springer.com/article/10.1007%2Fs00213-018-5034-1Cannabidiol enhances morphine antinociception, diminishes NMDA-mediated seizures and reduces stroke damage via the sigma 1 receptor.
“Cannabidiol (CBD), the major non-psychotomimetic compound present in the Cannabis sativa plant, exhibits therapeutic potential for various human diseases, including chronic neurodegenerative diseases, such as Alzheimer’s and Parkinson’s, ischemic stroke, epilepsy and other convulsive syndromes, neuropsychiatric disorders, neuropathic allodynia and certain types of cancer. CBD does not bind directly to endocannabinoid receptors 1 and 2, and despite research efforts, its specific targets remain to be fully identified. Notably, sigma 1 receptor (σ1R) antagonists inhibit glutamate N-methyl-D-aspartate acid receptor (NMDAR) activity and display positive effects on most of the aforesaid diseases. Thus, we investigated the effects of CBD on three animal models in which NMDAR overactivity plays a critical role: opioid analgesia attenuation, NMDA-induced convulsive syndrome and ischemic stroke. In an in vitro assay, CBD disrupted the regulatory association of σ1R with the NR1 subunit of NMDAR, an effect shared by σ1R antagonists, such as BD1063 and progesterone, and prevented by σ1R agonists, such as 4-IBP, PPCC and PRE084. The in vivo administration of CBD or BD1063 enhanced morphine-evoked supraspinal antinociception, alleviated NMDA-induced convulsive syndrome, and reduced the infarct size caused by permanent unilateral middle cerebral artery occlusion. These positive effects of CBD were reduced by the σ1R agonists PRE084 and PPCC, and absent in σ1R-/- mice. Thus, CBD displays antagonist-like activity toward σ1R to reduce the negative effects of NMDAR overactivity in the abovementioned experimental situations.” https://www.ncbi.nlm.nih.gov/pubmed/30223868 https://molecularbrain.biomedcentral.com/articles/10.1186/s13041-018-0395-2]]>
Restored Self: A Phenomenological Study of Pain Relief by Cannabis.
“The scientific study of the role of