Neurotransmitters Involved With Cannabinoid Action

Cannabis is a complex mixture of cannabinoid molecules (over 61 have been identified) and other chemicals (of which 400 have been identified) with THC as the main active cannabinoid responsible for the psychotropic effects. All these chemicals may have a wide variety of mechanisms of action and that of their metabolites may well be different again. So far, studies have concentrated on THC and a number of synthetic analogues, revealing a number of possible mechanisms of action. The central...

Future Prospects

Polls and voter referenda have repeatedly indicated that the vast majority of Americans think cannabis should be medically available and recent surveys in the UK have also reflected this attitude. In reviewing the potential for medicinal application of cannabis and its derivatives, one is hard-pressed to conclude that any of these related compounds would withstand rigorous, clinical trial and turn out to be effective alternatives to contemporary, established therapy. Two things are clear...

Neurological And Behavioural Effects

One of the most famous papers concerned with the adverse effects of cannabis was written by Campbell and colleagues, and published in 1971. This group investigated the structure of the CNS in chronic cannabis smokers, who had taken the drug regularly for at least three years. Ten males, with an average age of 22 years, were subjected to air encephalography to measure the size of brain ventricles. The results showed significant enlargement of the lateral and third ventricles in cannabis users...

Marijuana Withdrawal Syndrome

The identification of a THC receptor and ligand, and the recognition of the effect retarded release of THC and its active metabolites may have on carry-over effects, may be of help in identifying and understanding a marijuana withdrawal syndrome. As recently as the publication of the American Society of Addiction Medicine's Principles of Addiction Medicine in 1994, authors in that work were reporting that, aside from mild increases in heart rate, blood pressure, and body temperature, no...

Effects on Anxiety and Insomnia

Cannabis smoking produces a relaxant effect which most users value and it has been suggested that the beneficial effects of cannabis and THC observed in neurological disorders such as motor tics, dystonias and Huntingdon's chorea are due to sedative and anxiolytic actions. In addition, sedation is by far the most common side effect of cannabis, and in particular THC, observed in clinical trials against a range of disorders. This has lead to the suggestion that cannabis and some cannabinoids may...

Antidiabetic Drugs

Cannabis increases appetite and so when taken regularly it may appear to reduce the effectiveness of antidiabetic medication by increasing carbohydrate intake. An investigation of healthy non-diabetic adults showed that smoked cannabis had no ill effects upon carbohydrate metabolism (Permutt et al., 1976 Weil et al., 1968). Monitoring of blood glucose levels revealed no episodes of hypoglycaemia amongst seven patients who had fasted for 24-72 hours beforehand. The smoking of cannabis was also...

References

Abboud, R.T. and Sanders, H.D. 1976 Effect of oral administration of delta-9-tetrahydrocannabinol on airway mechanics in normal and asthmatic subjects. Chest, 70, 480-485. Adams, M.D., Earnhardt, J.T., Martin, B.R., Harris, I.S., Dewey, W.L. and Raazdan, K.K. 1977 A cannabinoid with cardiovascular activity but no overt behavioural effects. Experientia, 33, 1204-1205. Ahmedzai, S., Carlyle, D.L., Calder, I.T. and Moran, F. 1983 Anti-emetic efficacy and toxicity of nabilone, a synthetic...

Distribution of Cannabinoid Receptors within the CNS

Results obtained in autoradiographic studies with rat brain and spinal cord indicate that the distribution pattern of specific binding sites for cannabinoids within the CNS is heterogeneous, unlike that for any other known receptor type and consistent with the known ability of cannabinoid receptor agonists to impair cognition and memory, to alter motor function and movement and to relieve pain Herkenham et al., 1990, 1991b . The highest concentrations of cannabinoid binding sites in rat brain...

India

The earliest record of cannabis in Indian literature is found in the Atharva Veda which may have been written as early as 2000 BC. 'Bhang' is referred to briefly. However, it is unclear whether this is a direct reference to cannabis or another sacred plant Chopra and Chopra, 1957 . Cannabis was known in India at least as early as 1000 BC because bhanga is mentioned in the Susruta, which dates to this period. It is advocated for the treatment of catarrh accompanied by diarrhoea, excess...

Botanical Features Of Cannabis

Flower Cannabis Sativa Microscopy

Despite the debate over the mono or polytypic status of the genus Cannabis, all cannabis plants are easily recognised by certain distinct common botanical characteristics. Early herbals Dodonaeus, Gerarde speak of two types of cannabis the seed bearing type and the barren type, which reflect the fact that the plant is dioecious i.e. that it bears male and female flowers on separate plants Figure 1 . The male plant bears staminate flowers and the female plant pistillate flowers which eventually...

Anti Asthmatic Activity

Early reports indicated that acute inhalation increased airway patency in healthy individuals Tashkin et al., 1973 Vachon et al., 1973 Shapiro and Tashkin, 1976 and improved specific airway conductance in asthmatics Tashkin et al., 1974, 1975b Vachon et al., 1976 . However, there is good evidence that chronic smoking of cannabis restricts the airways and that, as with tobacco, unspecified irritants in the smoke can cause bronchospasm Henderson et al., 1972 . Aerosolised preparations of THC have...

Cannabinoid Receptor Agonists with Selectivity for CBX or CB2 Receptors

Cb1 Cb2 Receptors

Many established cannabinoids exhibit little difference in their affinities for CB1 and CB2 receptors Table 1 . These include delta-9-THC, CP 55,940 and anandamide. However, there are several recently developed compounds that do show significant selectivity for CB1 or CB2 receptors Table 1 . Apart from the antagonists, SRI41716A and LY320135 Section 3.2.1 , compounds with greater affinity for CB1 than CB2 receptors include three synthetic analogues of anandamide methanandamide, O-585 and O-689...

Info

Note 1 Class A of the UK MDA primarily differs from class B in maximum penalty on conviction but there is also a chemico-forensic difference in that the UN 1961 Convention clause, which generically extends control to esters or ethers of controlled substances, in the MDA only applies to class A substances. Note 2 Substances listed in the UK Misuse of Drugs Regulations 1985 MDRegs. Schedule 1 i.e. those not in medical use and in section 1 of Schedule 2 which are or might have been medically...

Persia And Arabia

Cannabis has had a long association with Persia and Arabia. Indeed the term hashish is Arabian and is taken from the phrase hashish al kief dried herb of pleasure . Several early manuscripts describe the popular use of cannabis for intoxication or medicinal purposes. In the Makhsanul aldawaiya, an ancient Arabic drug formulary, cannabis is described as a cordial, a bile absorber, and an appetizer, and its moderate use prolongs life. It quickens the fancy, deepens thought and sharpens judgement...