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Cannabis is a genus of flowering plant that includes one or more species. It is also known as hemp, although this term usually refers to Cannabis cultivated for non-drug use. As a drug it usually comes in the form of dried flowers (marijuana), resin (hashish), or various extracts collectively referred to as hash oil. Its use in this regard is documented more extensively in the article Cannabis (drug).
Species
The genus Cannabis was formerly placed with nettles in the family Urticaceae or with mulberries in the family Moraceae, but is now considered along with hops (Humulus sp.) to belong to the family Cannabaceae. Whether the different strains of Cannabis constitute a single species (Cannabis sativa L.) or multiple species has been a contentious issue for well over two centuries.[1][2]
Ernest Small conducted a taxonomic investigation of Cannabis and concluded that there is only a single species with two subspecies, sativa and indica, each divisible into a cultivated and a wild variety.[3] According to this concept, C. sativa subsp. sativa was selected for traits that enhance fiber or seed production and has low levels of the psychoactive delta-9-tetrahydrocannabinol (THC), whereas C. sativa subsp. indica was primarily selected for drug production and has relatively high levels of THC.
Botanists Richard E. Schultes and Loran Anderson also conducted taxonomic studies of Cannabis, and concluded that sufficient evidence exists to support recognition of three species, Cannabis sativa, Cannabis indica Lam., and Cannabis ruderalis.[4][5][6] According to their species descriptions, C. sativa is tall and laxly branched with relatively narrow leaflets, Cannabis indica is shorter, conical in shape, and has relatively wide leaflets, and Cannabis ruderalis is short, branchless, and grows wild in central Asia. This concept was embraced by Cannabis aficionados who commonly distinguish narrow-leafed "sativa" drug strains from wide-leafed "indica" drug strains.
A recent study of genetic variation in Cannabis supports recognition of C. sativa and C. indica as separate species, although the existence of a third species, "C. ruderalis", is less certain. This study assigned hemp (fiber/seed) landraces and feral populations from Europe, central Asia, and Asia Minor to C. sativa. Cannabis indica includes both narrow-leafed drug (NLD) and wide-leafed drug (WLD) strains, as well as southern and eastern Asian hemp strains and feral Himalayan populations[7].
Pharmacology
The pharmacology of cannabis is complex, yielding a variety of compounds. The most important ones are the psychoactive cannabinoid Delta-9-Tetrahydrocannabinol (Δ⁹-THC), cannabidiol, and the degradation product cannabinol.
Δ⁹-THC
The best known component of cannabis is Δ⁹-THC, which contributes such beneficial effects as relaxation, euphoria, induced sense of novelty, concentration of attention, altered space-time perception, alteration of visual, auditory, and olfactory senses, and appetite stimulation.
Cannabis bred and cultivated for medicinal, spiritual, and recreational use typically has a high content of Δ⁹-THC, whereas cannabis grown for industrial purposes typically has a low content of Δ⁹-THC.
Cannabinoids
In addition to Δ⁹-THC, the term cannabinoids includes the non- psychoactive cannabinol, cannabidiol and cannabinolic acid. These latter compounds are thought to contribute certain beneficial effects of cannabis, such as cell protection, immunosuppression and anti-inflammatory properties.
They are distinguished as usually containing a 1,1'-di-methyl-pyrane ring, a variedly derivatized aromatic ring and a variedly unsaturated cyclohexyl ring and their immediate chemical precursors, constituting a family of about 60 bi-cyclic and tri-cyclic compounds.
Cannflavins
Cannabis also contains a related class of compounds, the cannflavins. These compounds have been suggested to contribute certain beneficial effects of cannabis, such as analgesia and anti-inflammatory properties, and as such are considerably more effective than aspirin.
These usually contain a 1,4-pyrone ring fused to a variedly derivatized aromatic ring and linked to a second variedly derivatized aromatic ring, and include for example the non-psychoactive cannflavins A and B.
The cannabinoid receptor system
Humans and animals have two types of cannabinoid receptors: CB1 and CB2. The activation of these receptors is responsible for several medicinal and psychotropic properties of consuming cannabis. The discovery of these receptors in the 1980s revolutionized the understanding of cannabis pharmacology, illuminating many long-term assertions of its medical efficacy, and suggesting possibilities for cannabis-derived pharmaceutical compounds developed for specific medical purposes.
Aspects of cannabis use
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Etymology
The name cannabis is thought to be of Scythian origin. Possibly it has an earlier origin in Semitic languages like Hebrew, in Exodus 30:23 God commands Moses to make a holy anointing oil of myrrh, sweet cinnamon, kaneh bosm, and kassia. In kaneh bosm (Hebrew kannabos or kannabus) kan means "reed" or "cane", while bosm means "aromatic". Greek translations of the Old Testament rendered kan as "reed", leading to possibly erroneous English translations as sweet calamus (Exodus 30:23), sweet cane (Isaiah 43:24; Jeremiah 6:20) and calamus (Ezekiel 27:19; Song of Songs 4:14).
Sara Benetowa of the Institute of Anthropological Sciences in Warsaw is quoted in the Book of Grass as saying:
The astonishing resemblance between the Semitic kanbos and the Scythian cannabis lead me to suppose that the Scythian word was of Semitic origin. These etymological discussions run parallel to arguments drawn from history. The Iranian Scythians were probably related to the Medes, who were neighbors of the Semites and could easily have assimilated the word for hemp. The Semites could also have spread the word during their migrations through Asia Minor.
Comparing the English word hemp and the Greek word kannabis shows that the word came down from the Common Indo-European language. Words like kanapish for "hemp" occur in some Finno-Ugrian languages. It is likely that, soon after agriculture started, hemp as a cultivated plant spread widely, carrying its name with it.
External Links
References
- ^ Emboden, W. A. 1981. The genus Cannabis and the correct use of taxonomic categories. J. Psychoactive Drugs 13: 15–21.
- ^ Schultes, R. E., and A. Hofmann. 1980. Botany and Chemistry of Hallucinogens. C. C. Thomas, Springfield, IL., pp. 82–116.
- ^ Small, E., and A. Cronquist. 1976. A practical and natural taxonomy for Cannabis. Taxon 25: 405–435.
- ^ Schultes, R. E., et. al. 1974. Cannabis: an example of taxonomic neglect. Harvard University Botanical Museum Leaflets 23: 337–367.
- ^ Anderson, L. C. 1974. A study of systematic wood anatomy in Cannabis. Harvard University Botanical Museum Leaflets 24: 29–36.
- ^ Anderson, L. C. 1980. Leaf variation among Cannabis species from a controlled garden. Harvard University Botanical Museum Leaflets 28: 61–69.
- ^ Hillig, K.W. 2005. Genetic evidence for speciation in Cannabis (Cannabaceae). Genetic Resources and Crop Evolution 52: 161-180.
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