Cannabis indica
INTRODUCTION :
Cannabis is one of man's most ancient cultigens. It has probably been valued for its psychoactive- and medicinal properties since prehistoric times in Mesopotamie5. In ancient China, under emperor Shen Nung (± 2700 b Chr.), the plant was used medicinally against rheumatism and malaria, but they must also have been aware of its psychoactive properties because Shen Nung once wrote about the plant: 'if one uses it chronically, it will bring people in contact with the spirits and lighten the body' In ancient India hashish was valued for its intoxicating effects; Sanskrit domuments record it as as a medicine since 1400 b.Chr.5. According to Herodotus, the scytes (an Asian People that lived ± 800 b. Chr.) burned cannabis seeds and leaves on hot stones and inhaled the smoke to achieve the intoxicating effects1,4. In ancient Egypte, a drink with opiumlike properties was said to be prepared from the plant and in Jerusalem (± 400 b. Chr.) Cannabis has probably been used as an aneasthetic for pregnancies. Effects
Administration of Cannabis results in a dreamy state of consciousness in which one experiences feelings of extreme well being (euphoria), exaltation and inner joyousness, but sometimes also states of panic, paranoia and rage. Alterations of time-, space- and the 'sense' perceptions can be experienced. Cannabis also possess fantasy-enhancing properties (ideas are uncontrolable, plentiful and easily disrupted).
The psychological effects depend largely on the manner of administration: inhalation produces sedating, euphoric and weak hallucinations, whereas oral administration produces more mind expanding, psychedelic effects9. In higher doses one experiences very vivid visual- and auditory hallucinations (these are often pleasant and may have sexual overtones)3.
Chronic administation may result in psychological dependance, insomnia, and apathy.
Autonomic effects: blood-shot eyes, decrease of blood pressure, anti-glaumcome effect, dilatation of the bronchial tree, stimulation of appetite and anaesthetic properties.
Duration :
When smoked, the effects start within a few seconds and last up to four hours. When cannabis is imbibed as a tea or eaten (for example in the form of a cake), the effects start within an hour after ingestion and last for four to ten hours.
Dosage and preparation :
Marihuana (the female flowering tops), hashish (resin of the plant) and hash oil (an alcoholic extract) can be used in psychoactive preparations5. Hashish can be obtained by sieving the rough plant material, hash oil can be obtained by an extraction process of the plant material with ethanol.
These Cannabis products can be prepared in various ways: they can be inhaled (smoked/ vaporized), imbibed as a tea and eaten. A psychoactive tea can be prepared by boiling the cannabis product with a lump of butter in water for a quarter of an hour; when the product is eaten it can be made into a dish (for example cake, or an omlet), but it can be also administered solely.
The effects of Cannabis can be altered and intensified by combining it with a large variety of other psychoactive plants and mushrooms; Nicotiana tabacum, Papaver somniferum, Peganum harmala, Scutellaria latiflora (scullcap), Atropa belladonna, Datura species and hallucinogenic mushrooms influence the sedating, hallucinogenic and euphoric effects.
Figure: Marihuana
The psychoactive doses varies significantly per person, but in general 0.25-2.0 grams of marihuana should be effective. When D9-THC is inhaled it is active in doses of 2-22 mg and when taken orally between 20-90 mg; 1-3 % of D9-THC is present in dried plant material.
Botanical aspects :
The Cannabis genus belongs to Cannabaceae and comprises of three species: C. indica, C. sativa and C. Ruderalis. C. indica is native to the temperate parts of Central Asia and the Middle East, but now distributed throughout the entire world3,5. C. indica is an annual herb that has leaves consisting mostly of 8-10 leaflets, produces very fragrant and resinous flowering tops and grows 1.5 meters in height.
The plant's life-cycle is based on photoperiods: when the photo-period is more than 14 hours the plant will grow and when the photo-period is less than 12 hours, the plant will blossom and set seed. The little brown seeds can easily be germinated because the seeds merely need a moisture environment and a moderate to warm klimate (15-30 °C); it is possible to germinate the seeds in some cotton-wool and transfer them when the seedcoats have opened, but rhey can also be planted directly into the ground. C. indica can also be cultivated through cuttings5.
Phytochemistry :
The resin of marihuana contains cannabinoids (more than 60 compounds), alkaloids (choline, trigonellin, piperidine, betaine, proline, hordenine, cannabisativine), flavonoids and an aromatic oil consisting of eugenol, guaiacol, humulenes, sesquiterpenes, caryophylles and limonenes.
The cannabinoids (present as an oily mixture) are considered to be the active ingredients of the resin; although more than 60 cannabinoids are present in the resin, merely a few of them are responsible for the typical cannabis intoxication: Delta-9-tetrahydrocannabinol (D9-THC), cannabidiol (CBD), cannabinol (CBN), Delta-8-tetrahydrocannabinol (D8-THC), cannabichromen (CBC), cannabigerol (CBG) and tetrahydrocannabivarin (D9-THCV)8. 'Deltax' merely indicates the position of the double bond in the chemical structure; as a consequence of the nomenclature 'Delta-1' and 'Delta-9' are interchangeable.
In the cannabis plant approximately 95 % of the cannabinoids is present in the form of psychologically inactive carboxylic acids A and B (respectively, 4- CO2H-D9-THC and 2-CO2H-D9-THC), but during drying, storage and extraction these inactive compounds are converted into the psychoactive compounds. The dried plant material (foliage and flowering tops) contains 1-3 % D9-THC, hash oil contains 30-50 % D9-THC.
Pharmacology :
The psychoactive cannabinoids exert their effects by acting upon the CB-system (cannabinoid-system); in vivo these compounds act as agonists on CB1-receptors. It appears that the trans-isomers merely have affinity for the receptors, the cis-isomers not5. In addition, the (-)-enantiomers are 10-100 more potent than the (+)-enantiomers.
D9-THC (delta-9-tetrahydrocannabinol) is mainly responsible for the psychoactive effects, but D8-THC (delta-8-tetrahydrocannabinol), D9-THCV (tetrahydro-cannabivarin), CBC (cannabichromen), CBG (cannabigerol) and cannabivarinchromen are also active. It appears that D8-THC is 3/4 times less potent than D9-THC. CBD (cannabidiol) possesses antibiotic properties and counteracts the psychoactive effects of THC.
The G-protein-coupled-CB-receptors inhibit adenylylcyclase, block calcium-ionchannels and activate potasium-ionchannels in a similar manner as the three opiate-receptor-subtypes m, d and k. The natural ligands (agonists) of these receptors are probably amides and esters of unsaturated fatty acids, for example anandamide (2-arachidonyl-ethanolamide).The CB1-receptors are present in high densties in the basal ganglions, hippocampus and cerebellum. Shortage of anandamide in the nervous system leads to multiple sclerosis.
The lipophilic D9-THC is metabolised in the liver. Approximately 70 % of the orally ingested D9-THC is excreted by the intestine (the two main metabolic products are the psychoactive 11-OH-D9-THC and the psychologically inactive 11-CO2H-D9-THC) and 30 % by renal distretion (main excretion product is THC-CO2H glucuronide). 2,5
Modifiers
- Cannabis produces synergy with various hallucinogens (hallucinogenic mushrooms, -cactii, extacy, ayahuasca etc.).
- Tropane alkaloids (Atropa belladonna, Hyoscyamus niger and various datura and Brugmansia species) produce intensified reaction.
- Alcohol increases sedativity and results in severe impairment of driving performance.
- The psychoactive effects of harmala alkaloids are altered (Peganum harmala and Banisteriopsis species).
- Opiates (Papaver somniferum) also influence Cannabis' effects5.
- Tabacco (Nicotiana tabacum) increases sedativity.
References
1. [Balick/ Cox, 1998]
2. [Forth/ Henschler/ Rummel/ Fostermann/ Starke, 2001]
3. [Hoffmann/ Schultes, 1973]
4. [Hoffmann/ Schultes, 1970]
5. [Ratsch, 1998]
6. [Reko, 1949]
7. [Stafford, 1974]
8. [Trachsel/ Richard, 2000]
9. [Wells, 1973]
10. [Fessenden/ Fessenden, 1998]
11. Robbe, H.
Marihuana's impairing effects on driving are moderate when taken
alone but severe when combined with alcohol; Hum. Psychopharmac. Clin. Exp. 13, S70-S78 (1998)
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