PLANTS AND PEOPLE
Hugh D. Wilson 

Medicinals and Intoxicating Plants

What is a YAM and what does this have to do with birth control pills?

Dioscorea sp. (Dioscoreaceae) monocot - animal hormones have a steriodal backbone - synthesis is difficult, extraction from animal tissue complex - THUS, use - as a base for hormone synthesis - a plant steroid skeleton - big producers are 'yams' (Dioscorea - local 'wild yam') - 'SAPONINS' - soapy when extracted with water - DIOSGENIN - extracted from tubers of some Dioscorea mexicana - starting point for modern prodution of birth control pills, fertility drugs, cortisone and hydrocortisone [allergic reactions, arthritis]

Digitalis purpurea (Scrophulariaceae) - purple foxglove - William Withering - British physician - carefully examined an old european folk cure for heart trouble - led to widespread medical use of Digitalis - later steroids 'cardiac glycosides' were isolated and characterized - change heart rythms - not synthesized - three steroids currently isolated (digoxin).

Papaver somniferum [Papaveraceae] - native to eastern europe and western asia - ancient use in the near east - mostly as a narcotic - today - ca. 4% of total world production is used for legitimate medical reasons. - latex produced in the pericarp of the immature capsule - contains 26 different alkaloids. Most important medically:

    MORPHINE: isolated in 1803 - major item for surgery - only source of general anesthetic [earlier either drunk or strapped to the table] - many other synthetics available today - only administered in cases of extreme pain - addictive

    CODEINE: milder, non habit forming - can be synthesized - used in over the counter and prescription drugs

    PAPAVERINE: 'paragoric' of the old days [solution of opium]- now used in several commercial products.



Drugs - altered perceptions:

Drugs are generally classified by effect but this is often difficult and results in ambiguity. Many drugs can produce more than one effect, depending on the quantity taken.

1. Behavior stimulants - cocaine caffeine, nicotine.
2. Convulsant - strychnine (Strychnos - Loganiaceae)
3. Narcotic analgesics - opium, morphine, codeine
4. Psychedelics - THC, mescaline, atropine, scopolamine, LSD
5. Antipsychotic agents - resperine (Rauwolfia serpentina - Apocynaceae)
6. Sedatives and hypnotic compounds - alcohol

Most psychoactive compounds contain nitrogen and most are alkaloids. THC, alcohol, LSD and hallucinogenic terpenes are exceptions.

MODE OF ACTION

1. Absorption - orally, injection, membrane absorption.

2. Most act on CNS, drugs reach brain faster than other tissues but passage of chemicals into brain tissue is more difficult than in other parts of body.

3. Alter interactions between neurons. Neurons transmist information chemically via neurotransmitters which can cross the synapse between neurons. Sites in the receptor neuron recognize compound and bind with it, which causes a response in receptor. Psychoactive drugs alter or mimic 5 kinds of neurotransmitters: acetylcholine; norepinephrine; dopamine, serotonin; neuropeptides. There are some exceptions, the mode of THC is unclear, caffeine activates intracellular metabolism, alcohol is CNS depressant.

DRUG USAGE

1. Drug usage in human cultures is very ancient and was - in prehistoric times - often associated with religious and cultural ceremonies and customs. American cultures, compared to European, employed a more diverse suite of plants for this purpose (40 vs. 6 species), although this might reflect biocultural homogeneity as opposed to levels of usage.

2. Reasons for drug usage, including ethanol, in modern society are complex and poorly understood but, given the deep historical precedent, there seems to be a basic human need to alter 'base level' conditions via intoxicating substances. Of psychoactive compounds in use today, ethanol is - by far- the most widely used. Next comes caffeine, then nicotine.

Tobacco played a part in prehistoric native American ritural and, in isolated areas of native American culture, this use remains. Two species (Solanaceae) where utilized, Nicotiana tabacum, of the tropics and N. rustica (now almost extinct) from North America North of Mexico. European usage was initially populatized in France (Jean Nicot - French ambassador to Portugal at the time), mostly as a medicinal, and extended by the British, especially to its North American colonies where it remains today as an important (and legal) element of the U.S. economy supported via price supports and export promotion by the U.S. government. Nicotine is a tropane alkaloid typical of many others found among taxa of the Solanaceae: Datura (New World native - scopolamine - most hallucinogenic (and dangerous but also used as a medicinal - seasickness) of the solanaceous alkaloids, also atropine, found in belladonna (Atropa belladonna) and many other Old World species of the family produces intoxicating effects that have produced a rich lore (witchcraft, medicine, herbals, etc.).

Cocaine - Erythroxylum coca - Erythroxylaceae - at least 3K BP in the Andes - used only by native Andeans until active ingredent, the alkaloid cocaine isolated in 1860 - popularized as a medical drug by Sigmund Freud in the 1880s (local anesthetic, psychotherapy) - coca wine developed in Italy in 1860 and coca-cola - which included coca and cola (Cola nitida - Sterculiaceae) extracts was 1st marketed in 1886 as a headache remedy - federal law prohibited use in beverages in 1904 - evidently coca leaves [with cocaine removed] still used in the production of coca-cola.

Marijuana - Cannabis sativa - Cannabaceae - multi-use plant, fiber, oil, edible seed (used to be sold in bird seed mixtures), and drug - one of the most ancient and widely distributed elements of the ethnoflora. Dioecious annual - association with humans so intense that origins are very difficult to determine. Known in China as 'ma' and probably originated there - hemp fiber was used in the first true paper (105 AD) - Chinese apparently were focused on medicinal use - 5K BC chinese noted greater proportion of creative principals in the pistillate plant - India - 1st to maximize use as a drug ('Bhang' - Bengal = Bhangland - milk-based beverage concocted with ground Cannabis leaves and spices) - resin, produced in specialized glands that are most highly concentrated on floral bracts of the pistillate inflorescence, an adaptation to dessication. Thus, Indians planted widely separated (to maximize branching [as opposed to Chinese fiber production]) fields of pistillate plants (removed staminate) without irrigation - 'sinsemilla' (unfertilized, without seed) - HASHISH = pure resin - 1st word of Cannabis to the west came with Marco Polo - 1297 AD - introduced to Africa in the 15th and 16th centuries by the arabs, spread to Europe in late 1700s, entry into the new world in mid-1500s by Spanish, to Jamaica from British in 1800, african slaves - familiar with the plant after arab introduction to Africa 2-300 years earlier, found a familiar plant. Use in the US expanded during prohibition - banned in several states in the 20s and 30s, taxed - but not banned - in 1937 by fed. gov. - later established as a 'controlled sustance' - boom in US during the 1960s which continues today. Taxonomic/legal situation in the 60s/70s: C. indica, C. sativa, C. ruderalis - studies during he 70s and 80s recommended removal of legal sanctions, but now part of the massive anti-drug "war".

Papaver somniferum - Papaveraceae - started use in the near east, at least 5K BP, not known in Asia until 1200 BP - Dutch introduced the practive of smoking opium (raw latex) and tobacco in the 1600s to formosa - later spread throughout asia - English supplied opium, grown on british plantations in India, to China [illegal in England] - oprium wars [1800s] - did not completely end until 1949 [Peoples Republic of China]. Not used in Europe until early 1500s - Laudanum = raw opium dissolved in alcohol.

1803 - morphine isolated - pure, could be dosed - 10X stronger than opium (contains at least 24 active alkoloids) - hypodermic needle (1853) = ideal pain killer - dangers of addiction recognized - in this country after the civil war

Attempts to produce non-addictive pain killer - chemical alteration of morphine - semi-synthetic - heroin - originally thought to be non-addicting - declared illegal in US in 1924 - following pact with Turkey in 1972 - current US supply of opium comes from asia - what goes around comes around.

Peyote - Lophophora williamsii - Cactaceae - mescaline - spineless cactus of the Rio Grand valley - native to Texas and northern Mexico- originally used by the native Mexicans of the central plateau - supressed by the spanish - retain by remote tribes of northern Mexico and recently extended to plains indians - North American Church - both the plant and the compound declared illegal - church exempt.

LSD

Ipomoea tricolor - (Convolvulaceae) - Morning glory. Seeds contain LSD (D-lysergic acid amide), very dangerous since seeds are toxic. Synthetic form of LSD is 10X as potent as natural form but clear example of convergence in that LSD is associated with the fungus (ergot) - Claviceps purpurea - that infects rye (ergotism). 


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29 Nov 2010