There are at least 500 natural compounds found in Cannabis plants, of which up to 80 have been classified as cannabinoids – chemicals unique to the plant. (according to Cannabis Information and support Australia.) The most well known and researched of these, delta-9-tetrahydrocannabinol (delta 9 THC), is the substance primarily responsible for the psychoactive effects of cannabis.
The effects of THC are believed to be moderated by the influence of the other components of the plant, most particularly other cannabinoids. CBD is known to make a THC high more mellow. Strains of cannabis that are especially high in CBD don’t cause a “high” like THC.
The cannabinoids are often separated into subclasses:
- cannabigerols (CBG)
- cannabichromenes (CBC)
- cannabidiols (CBD)
- tetrahydrocannabinols (THC)
- cannabinol (CBN) and cannabinodiol (CBDL)
- other cannabinoids (such as cannabicyclol (CBL), cannabielsoin (CBE), cannabitriol (CBT) and other miscellaneous types)
What do cannabinoids do?
Cannabinoids affect the user by interacting with specific receptors, located within different parts of the central nervous system. Two kinds of cannabinoid receptors have been found to date and are termed CB1 and CB2. A substance that occurs naturally within the brain and binds to CB1 receptors was discovered in 1992 and termed ‘anandamide’. Additional naturally occurring substances that bind to CB1 have since been discovered, and these, together with the receptors are termed the endocannabinoid system. CB1 and CB2 receptors are not only found in the brain, but throughout the body.
What are the differences between cannabinoids?
The major differences between the cannabinoids are determined by the extent to which they are psychologically active. Three classes of cannabinoids, CBG, CBC and CBD are not known to have a psychoactive effect. THC, CBN, CBDL amongst other cannabinoids, are known to be psychologically active to varying degrees. A few of the most studied cannabinoids include:
- THC – Tetrahydrocannabinol is the cannabinoid mostly responsible for the marijuana high. THC binds directly to the CB1 receptors in the brain and body.
- THCA is the “acid” form of THC. Much of the THC in cannabis is stored in the acid form and requires heat before it is converted to THC. The process of heating THCA to get THC is known as decarboxylation. Before making edibles from marijuana it is necessary to “decarb” the plant material. THCA has anti-inflamatory and anti-seizure properties. It is neuroprotective and may fight cancers such as prostate cancer. Read more about THCA here.
- CBD – Cannabidiol appears to have anti-anxiety effects and it can lessen the psychoactive effects of THC. This means that a plant with a greater percentage of CBD may reduce the intensity of the effects of THC, which in effect, lowers the potency of the plant. Use of a cannabis plant with less CBD has been shown to have an increased psychological impact and result in unwanted effects such as anxiety. CBD does not bond directly to either CB1 or CB2 receptors but it appears to increase the level of natural cannabinoids (endocannabinoids). It has anti-tumor activity in prostate cancer.
- CBDA is the “acid” form of CBD. Like THCA, much of the CBD in cannabis is stored in the acid form and requires heat before it is converted to THC. Before making edibles from industrial hemp it is necessary to “decarb” the plant material
- CBN – When THC is exposed to air it oxidizes and forms CBN. CBN is only very weakly psychoactive and not unlike CBD, interacts with THC to reduce its effects. This is why cannabis that has been left out unused will have increasing amounts of CBN and decreasing amounts of THC and thus lose potency. CBN increases appetite without the heavy psychoactive effect of THC..
- CBG – Cannabigerol is non-psychoactive but still contributes to the overall effects of Cannabis. CBG has been shown to promote apoptosis (cell death) in cancer cells and inhibit tumor growth in mice.
- THC-V – Tetrahydrocannabivarin is common in certain central Asian and southern African strains of cannabis. It is an antagonist of THC at CB1 receptors and lessens the psychoactive effects of THC
- CBD-V – closely related to CBD, this cannabinoid is being studied for its anti-seizure properties.
-based on material from Cannabis Information and support Australia and other sources.