Article by Dr. Frank, Cannabis Culture
Cannabis doesn’t seem to work on the same area of the brain that codes for the sensation of pain like opiates and opioids do, but rather the part of the brain that regulates our emotions and how we react to pain.
This has sparked a debate, one side argues cannabis a pain killer, while others label the plant based therapies as “pain distractors.”
Are we just playing with semantics at the moment? Could cannabis not in fact be an actual pain killer – it’s just that we don’t fully understand all the mechanisms that cause pain? This is certainly possible, and cannabis research is certainly putting to question what we traditionally thought pain was. To look at how cannabis beats pain, we ought to look at what areas of the body it effects as far as we know so far …
There are two main cannabinoid receptors located throughout the body: CB1 receptors, which are found mostly in the central nervous system (CNS), but also the lungs, liver and kidneys; and CB2 receptors, which are found in the peripheral nervous system (PNS), and in expressed the immune system and hematopoietic cells (stem cells that give rise to other types of blood cells). THC has an affinity for the endocannabinoid receptors; CBD has a low affinity for the body’s cannabinoid receptors, but influences the endocannabinoid receptors in a more “indirect” way and also has effects on other receptors in the body.
This paper, entitled ‘Role of the Cannabinoid System in Pain Control and Therapeutic Implications for the Management of Acute and Chronic Pain Episodes’ explains how cannabis helps manage pain more thoroughly, but to give the gist:
Cannabis regulates nociceptor thresholds. Nociceptors are receptors in the body that detect pain.
Cannabis also acts on non-nervous tissues as well as nervous tissues, which is why it can be so helpful for so many different types of pain, whether physical, mental or emotional.
THC and CBD can help control the pain signals being received by nociceptors
Cannabis can inhibit the release of proinflammatory factors by non-neuronal cells.
Cannabis Indirectly stimulates opioid receptors, in particular μ-opioid and δ-opioid receptors.
Cannabis can also work synergistically with opioids as well.
THC works on the endocannabinoid receptors, whereas CBD works on the vanilloid, serotonin and adenosine receptors and the endocannabinoid receptors in a less direct way.
To quote from the paper:
“Cannabinoid receptor agonists modulate nociceptive thresholds by regulating neuronal activity , but they also relieve pain by acting on non-nervous tissues. CB1 receptor is involved in the attenuation of synaptic transmission, and a proportion of the peripheral analgesic effect of endocannabinoids can be attributed to a neuronal mechanism acting through CB1 receptors expressed by primary afferent neurons. However, recent findings suggest that CB1 receptors are also present in mast cells and may participate in some anti-inflammatory effects. Thus, activated CB1 receptors present in mast cells induce sustained cAMP [cyclic adenosine monophosphate – a signal transmitter]elevation, which, in turn, suppresses degranulation [146 – “degranulation” is a cellular process that releases antimicrobial cytotoxic or other molecules from secretory vesicles called granules found inside some cells].
On the other hand, although CB2 receptors have been related traditionally to the peripheral effects of cannabinoids (mainly modulation of the immunologic responses), they also contribute to antinociception by inhibiting the release of proinflammatory factors by non-neuronal cells located near nociceptive neuron terminals. CB2 receptors are expressed in several types of inflammatory cells and immunocompetent cells. For that reason, activation of peripheral CB2 receptors generates an antinociceptive response in situations of inflammatory hyperalgesia and neuropathic pain [66, 160], while selective CB2 receptor agonists are not antihyperalgesic against chronic inflammatory pain in CB2 knockout mice .”
Remember though that many of these studies are on mice, and phytocannabinoids generally have different effects on humans.