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UVSS HEMPOLOGY 101 CLUB LESSON #6 : CANNABIS CHEMISTRY - Part 2 |
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It is important to keep in mind that marijuana is not a single drug. Marijuana is a mixture of the dried flowering tops and leaves from the plant cannabis sativa. Like most plants, marijuana is a variable and complex mixture of biologically active compounds. Characterizing the clinical pharmacology of the constituents in any pharmacologically active plant is often complicated, particularly when the plant is smoked or eaten more or less in its natural form. Marijuana is not unusual in this respect. Cannabis sativa is a very adaptive plant, so its characteristics are even more variable than most plants. Some of the seeming inconsistency or uncertainty in scientific reports describing the clinical pharmacology of marijuana results from the inherently variable potency of the plant material used in research studies. Inadequate control over drug dose when researching the effects of smoked and oral marijuana, together with the use of research subjects who vary greatly in their past experience with marijuana, contribute differing accounts of what marijuana does or does not do. Marijuana contains more than 400 chemicals. Approximately 60 are called cannabinoids; i.e., C21 terpenes found in the plant and their carboxylic acids, analogs, and transformation products. Most of the naturally occurring cannabinoids have been identified. Cannabinoids appear in no other plant. Cannabinoids have been the subject of much research, particularly since the mid 1960s when Mechoulam and his colleagues first isolated delta-9-tetrahydrocannabinol ( 9-THC). THC in the scientific literature is termed 9-THC or 1-THC depending on whether the pyran or monoterpinoid numbering system is used. Report to the Director, National Institutes of Health, by the Ad Hoc Group of Experts, 1997. Hashish is a concentrated conglomeration of "bubbles" that contain the most potent ratio of pure cannabinoids produced by the marijuana plant. These bubbles sit on top of a stalk like a golf ball sits on a tee. In cannagriculture lingo, this natural contraption is called a "capitate-stalked resin gland," also known as a "trichome." Cannabis also produces un-stalked resin glands that grow flush with plant surfaces, but the taller capitate stalked variety are the most desired by cannabis breeders, smokers and photographers. As marijuana flowers mature, the glands produce resinous substances unique to marijuana. This resin swells and expands to form round, clear capsules that glisten like crystals. Brady, cannabisculture.com. |
Cannabis sativa L. produces more than 60 terpeno-phenols that have not been detected in any other plant. One of these constituents, 9-tetrahydrocannabinol (THC) has been the object of thousands of publications, as it is by far the major psychoactive principle in marijuana and hashish. Cannabidiol (CBD), a nonpsychoactive component, has also been widely investigated due to its anti-inflammatory, antischizophrenic and antiepileptic properties. Surprisingly, the other plant cannabinoids have been mostly neglected. Cannabinoid acids, which are precursors of the neutral cannabinoids, such as THC and CBD, were shown to be antibiotic and were actually used for some time in veterinary medicine in Czechoslovakia about 50 years ago. Most of the other plant cannabinoids were assayed for possible psychoactivity. When none was found, interest in them waned. The discovery of the endocannabinoid system and the plethora of activities of the endocannabinoids raise the possibility that some of the plant cannabinoids may cause related effects. The best-known endocannabinoids, anandamide and 2-arachidonoyl glycerol, have been found to play a role not only in the central nervous system but also in most physiological systems that have been investigated – the immune, the cardiovascular, the reproductive, the respiratory, the skeletal systems, to name a few. Some of the activities are CB1/CB2 cannabinoid receptor-dependent, but many are not. Numerous additional receptors have been proposed. Is it possible that some of the plant cannabinoids, which are not psychoactive (and presumably do not bind to the CB1 receptor), are also active in these systems? PLANT CANNABINOIDS: A NEGLECTED PHARMACOLOGICAL TREASURE TROVE, by Raphael Mechoulam, 2005. CB1 and CB2 cannabinoid receptors are the primary targets of endogenous cannabinoids (endocannabinoids). These G protein-coupled receptors play an important role in many processes, including metabolic regulation, craving, pain, anxiety, bone growth, and immune function. Cannabinoid receptors can be engaged directly by agonists or antagonists, or indirectly by manipulating endocannabinoid metabolism. In the past several years, it has become apparent from preclinical studies that therapies either directly or indirectly influencing cannabinoid receptors might be clinically useful. Mackie, K., pubmed.gov. |
