Tag Archives: agonists

In vitro and non-invasive in vivo effects of the cannabinoid-1 receptor agonist AM841 on gastrointestinal motor function in the rat.

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“Cannabinoids have been traditionally used for the treatment of gastrointestinal (GI) symptoms, but the associated central effects, through cannabinoid-1 receptors (CB1R), constitute an important drawback. Our aims were to characterize the effects of the recently developed highly potent long-acting megagonist AM841 on GI motor function and to determine its central effects in rats…

The CB1R megagonist AM841 may potently depress GI motor function in the absence of central effects. This effect may be mediated peripherally and may be useful in the treatment of GI motility disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/26387676

A Cannabinoid Receptor 2 Agonist Prevents Thrombin-Induced Blood-Brain Barrier Damage via the Inhibition of Microglial Activation and Matrix Metalloproteinase Expression in Rats.

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“Thrombin mediates the life-threatening cerebral edema and blood-brain barrier (BBB) damage that occurs after intracerebral hemorrhage (ICH).

We previously found that the selective cannabinoid receptor 2 (CB2R) agonist JWH-133 reduced brain edema and neurological deficits following germinal matrix hemorrhage (GMH).

We explored whether CB2R stimulation ameliorated thrombin-induced brain edema and BBB permeability as well as the possible molecular mechanism involved.

The results demonstrated that JWH-133 administration significantly decreased thrombin-induced brain edema and reduced the number of Iba-1-positive microglia…

We demonstrated that CB2R stimulation reduced thrombin-induced brain edema and alleviated BBB damage.”

http://www.ncbi.nlm.nih.gov/pubmed/26376816

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

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“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

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

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“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

Cannabinoid-based drugs targeting CB1 and TRPV1, the sympathetic nervous system, and arthritis.

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“Chronic inflammation in rheumatoid arthritis (RA) is accompanied by activation of the sympathetic nervous system, which can support the immune system to perpetuate inflammation. Several animal models of arthritis already demonstrated a profound influence of adrenergic signaling on the course of RA.

Peripheral norepinephrine release from sympathetic terminals is controlled by cannabinoid receptor type 1 (CB1), which is activated by two major endocannabinoids (ECs), arachidonylethanolamine (anandamide) and 2-arachidonylglycerol.

These ECs also modulate function of transient receptor potential channels (TRPs) located on sensory nerve fibers, which are abundant in arthritic synovial tissue. TRPs not only induce the sensation of pain but also support inflammation via secretion of pro-inflammatory neuropeptides.

In addition, many cell types in synovial tissue express CB1 and TRPs.

In this review, we focus on CB1 and transient receptor potential vanilloid 1 (TRPV1)-mediated effects on RA since most anti-inflammatory mechanisms induced by cannabinoids are attributed to cannabinoid receptor type 2 (CB2) activation.

We demonstrate how CB1 agonism or antagonism can modulate arthritic disease.

The concept of functional antagonism with continuous CB1 activation is discussed.

Since fatty acid amide hydrolase (FAAH) is a major EC-degrading enzyme, the therapeutic possibility of FAAH inhibition is studied.

Finally, the therapeutic potential of ECs is examined since they interact with cannabinoid receptors and TRPs but do not produce central side effects.”

http://www.ncbi.nlm.nih.gov/pubmed/26343051

Pro-inflammatory obesity in aged cannabinoid-2 receptor deficient mice.

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“Cannabinoid-1 receptor signaling increases the rewarding effects of food intake and promotes the growth of adipocytes, whereas CB2 possibly opposes these pro-obesity effects by silencing the activated immune cells that are key drivers of the metabolic syndrome.

Pro- and anti-orexigenic cannabimimetic signaling may become unbalanced with age because of alterations of the immune and endocannabinoid system…

CB2 agonists may fortify CB2-mediated anti-obesity signaling without the risk of anti-CB1 mediated depression that caused the failure of rimonabant.”

http://www.ncbi.nlm.nih.gov/pubmed/26303348

Cannabinoid receptor type 1 agonist ACEA improves motor recovery and protects neurons in ischemic stroke in mice.

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“Brain ischemia produces neuronal cell death and the recruitment of pro-inflammatory cells.

In turn, the search for neuroprotection against this type of insult has rendered results involving a beneficial role of endocannabinoid receptor agonists in the Central Nervous System.

In this work, to further elucidate the mechanisms associated to this neuroprotective effect…

Motor tests showed a progressive deterioration in motor activity in ischemic animals, which only ACEA treatment was able to counteract.

Our results suggest that CB1R may be involved in neuronal survival and in the regulation of neuroprotection during focal cerebral ischemia in mice.”

http://www.ncbi.nlm.nih.gov/pubmed/26296704

http://www.thctotalhealthcare.com/category/stroke-2/

The emerging role of the endocannabinoid system in the pathogenesis and treatment of kidney diseases.

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“Endocannabinoids (eCBs) are endogenous lipid ligands that bind to cannabinoid receptors that also mediate the effects of marijuana.

The eCB system is comprised of eCBs, anandamide, and 2-arachidonoyl glycerol, their cannabinoid-1 and cannabinoid-2 receptors (CB1 and CB2, respectively), and the enzymes involved in their biosynthesis and degradation.

It is present in both the central nervous system and peripheral organs including the kidney.

The current review focuses on the role of the eCB system in normal kidney function and various diseases, such as diabetes and obesity, that directly contributes to the development of renal pathologies.

Normally, activation of the CB1 receptor regulates renal vascular hemodynamics and stimulates the transport of ions and proteins in different nephron compartments. In various mouse and rat models of obesity and type 1 and 2 diabetes mellitus, eCBs generated in various renal cells activate CB1 receptors and contribute to the development of oxidative stress, inflammation, and renal fibrosis.

These effects can be chronically ameliorated by CB1 receptor blockers.

In contrast, activation of the renal CB2 receptors reduces the deleterious effects of these chronic diseases.

Because the therapeutic potential of globally acting CB1 receptor antagonists in these conditions is limited due to their neuropsychiatric adverse effects, the recent development of peripherally restricted CB1 receptor antagonists may represent a novel pharmacological approach in treating renal diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/26280171

Synthesis and biological evaluation of (3′,5′-dichloro-2,6-dihydroxy-biphenyl-4-yl)-aryl/alkyl-methanone selective CB2 inverse agonist.

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“Cannabinoid receptor 2 (CB2) selective agonists and inverse agonists possess significant potential as therapeutic agents for regulating inflammation and immune function.

Although CB2 agonists have received the greatest attention, it is emerging that inverse agonists also manifest anti-inflammatory activity.

In process of designing new cannabinoid ligands we discovered that the 2,6-dihydroxy-biphenyl-aryl methanone scaffold imparts inverse agonist activity at CB2 receptor without functional activity at CB1. To further explore the scaffold we synthesized a series of (3′,5′-dichloro-2,6-dihydroxy-biphenyl-4-yl)-aryl/alkyl-methanone analogs and evaluated the CB1 and CB2 affinity, potency, and efficacy.

The studies reveal that an aromatic C ring is required for inverse agonist activity and that substitution at the 4 position is optimum. The resorcinol moiety is required for optimum CB2 inverse agonist activity and selectivity. Antagonist studies against CP 55,940 demonstrate that the compounds 41 and 45 are noncompetitive antagonists at CB2.”

http://www.ncbi.nlm.nih.gov/pubmed/26275680

Neuropeptide VF Enhances Cannabinoid Agonist WIN55,212-2-Induced Antinociception in Mice.

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“Cannabinoids produce analgesia in several pain models, but the undesirable side effects from high doses of cannabinoid drugs limit their clinic use.

Our recent results indicate that cannabinoid-induced antinociception was enhanced by neuropeptide VF (NPVF).

Here, we investigate whether low-dose cannabinoid agonists combined with NPVF can produce effective antinociception with limited side effects…

These data suggest that the cannabinoid agonist combined with NPVF produces effective antinociception-lacking tolerance via both cannabinoid receptor type 1 and neuropeptide FF receptors in the brain.”

http://www.ncbi.nlm.nih.gov/pubmed/26273748