Psychoactive Plants

Psychoactive Plants

Stimulants - III: Other Stimulants

Stimulants

Cocaine

Ephedrine

Nicotine

Khat - cathonine

Betel nuts - arecoline

Caffeine

Khat

Khat: stimulant from Catha Edulis

Alkaloids

Khat contain cathinone and cathine, twophenylisopropylamine alkaloids which resembleamphetamine –

Cathinone is the main alkaloid

Produces amphetamine-like action - effects not distinguishable fromamphetamine - a naturally occurring amphetamine - carbonyl groupreplaces methylene side chain

Drug conditioned animals cannot distinguish cathinone fromamphetamines

Khat consumption induces mild euphoria and excitement,reduces appetite, increases heart rate and blood pressure

Withdrawal symptoms can follow prolonged khat use includelethargy, depression, nightmares and tremor

Cathinone

Functions by releasing catecholamines (esp.dopamine) from presynaptic storage sites

Cathinone only present in fresh leaves – itdegrades within 48 hrs

After this time only cathine left

Cathine also a stimulant but has a lower potentialfor abuse

Amphetamine

Meth-amphetamine

Cathinone

Cathine

Ephedrine

Pseudoephedrine

Betel Nuts

Betel nuts from the betel palm Areca catechu

Traditional Use

Long history of use in Asia - recorded in 4th centuryin China

Traditionally chewed

Crushed betel nuts (from the betel palm) wrapped inpieces of betel leaf from the betel vine, Piper betel(in the pepper family - Piperaceae) along with limeand sometimes other flavorings

Lime (CaCO3) needed to release alkaloid

Arecoline

Many active ingredient in betel nuts is thealkaloid arecoline - although betel nuts haveseveral other alkaloids

Arecoline has also been shown to improvelearning and memory

Also traditional use for intestinal worms

Used as an antihelminthic in veternary medicinetoday

Mode of Action

Not completely understood

Believed to affect the central and autonomic nervoussystems - increases plasma concentrations ofnorepinephrine and epinephrine

Evidence suggests also an inhibitor of GABA(gamma aminobutryc acid) uptake

Also Piper betel leaf contains aromatic phenoliccompounds which have been found to stimulate therelease of catecholamines in vitro

Effects of Betel Chewing

Stains mouth

Possible carcinogen

Betel chewing associated with throat, mouth, andesophagal cancers

Betel chewing spreading

Lime (CaCO3) needed to release arecoline

However some chew it only for flavor not stimulatingeffect

Also mixed with tobacco and it strongly interacts withtobacco

Caffeine

Coffee and Caffeine

Made from seeds of Coffea arabica in theRubiaceae

Seeds occur in coffee berries (cherries ofcommerce)

Flowers and berries ofCoffea arabica

Coffee berries are picked by handby worker in Columbia

Coffea arabica native to Ethiopia

Ethnobotany and history

Long history of use in Arab world

Introduced to Europe in 1615

By 1700 coffee houses popular throughoutEurope

Dutch established plantations in East Indieslate in 17th century

East Indies  Paris and Amsterdam Caribbean Islans  South America

Caffeine

Caffeine occurs naturally in the leaves, seeds or fruitof more than 60 plant species, of which coffee,cocoa-beans, tea, cola and guarana are the bestknown

Like other stimulates, caffeine acts on CNS -noradrenergic receptors (norepinephrine)

Promotes alertness and endurance

Constricts blood vessels

Increase heart beat

H = theophylline

H = theobromine

Caffeine Content of Common Products

Drip coffee.....115 mg

Tea..................40 mg

Cocoa..............13 mg

Coca Cola........46 mg

Diet Coke.........46 mg

Dr. Pepper........40 mg

Mr. Pibb............41 mg

Mt. Dew............54 mg

Pepsi...............38 mg

Surge...............51 mg

Jolt Cola...........71 mg

Excedrin...........65 mg

Anacin..............32 mg

NoDoz............100 mg

Vivarin............200 mg

Midol...............60 mg