Transcript Opium Poppy - Thblack.com

Opium Poppy
Opium Poppy: Papaver somniferum
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Member of the Papaveraceae, poppy
family
Large showy annual with conspicuous
flowers (white, pink, red, purple)
Fruit is a capsule that produces latex
with several potent alkaloids
Latex is collected from cut capsules
(latex oozes out and dries – dried latex
scraped off) - dried latex called opium
Fresh capsule of opium
poppy
Cut capsule showing
latex exuding from cut
Opium Poppy
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Native to the Mediterranean area
Oldest evidence of poppy use was
existence of a poppy capsule found with
religious artifacts from a cave in Spain
that are dated 7500 years old
Evidence of spread in Europe from 3000
to 5000 years ago
Reasons for use at these sites unknown
Ancient medical use
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Poppy was revered by several ancient
societies for its analgesic properties and
its ability to induce sleep
Opium latex has a long history of use
for pain relieve and inducing sleep
among Babylonia, Egyptian, Greek, and
Roman civilizations
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Opium eaten, drunk, and smoked
Most common method was to dissolve opium in
alcohol – opium wine
Mediterranean societies
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Writings of Hippocrates, Theophrastus,
Dioscorides, and Galen show evidence
of the widespread use of opium
In eastern Mediterranean it seems that
poppy also became valued for its
narcotic use
Ancient goddess of Crete is depicted
wearing a crown with 3 poppy capsules
Opium Alkaloids
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Many alkaloids have been identified in opium
latex (opiates) - maybe as many as 50
Morphine and codeine most important
Morphine first alkaloid identified from any
plant in 1806 and the pain relieving
properties soon recognized
Morphine (like raw opium) is strongly
addictive and because of this its general
medical use declined in 20th century
Still drug of choice for cases of severe pain
Morphine
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Morphine affects the central nervous
system but also induces drowsiness and
can depress respiration - overdose can
cause death through respiratory failure
Cause has high physical dependency
Has relatively low oral activity
Became drug of choice to treat war
injuries during Civil War - created many
addicts
Codeine
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Codeine most widely used opiate
Only 1/5 as strong as morphine and still
addictive
Effective in oral medication and often
used in combination with non-opiate
compounds
Codeine is especially effective in cough
syrups because it suppresses the
coughing reflex
Heroin
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In 1898, Bayer Pharmaceuticals introduced
heroin which they thought was a nonaddictive opiate and more effective than
morphine and codeine
Heroin is a semi-synthetic derivative of
morphine - diacetyl morphine
Widely available in over the counter tonics
and cough syrups from 1898 to 1914 - mail
order catalogs, etc
Heroin
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Within a few years over 1 million people
addicted to heroin in US alone
Soon realized that it was actually more
addictive than morphine - actually six times
more addictive
In US use of heroin is illegal placed under
Harrison Act of 1914
Heroin still used medicinally in other countries
Heroin addiction a major problem worldwide
Isoquinoline alkaloids
Opiates
Mode of action
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Opiates bind to opiate receptors in membrane
of neurons of the brain and spinal column
(ID’d in 1970s)
The natural ligands that normally bind to
these receptors are endorphins and
enkephalins (small peptides)
These peptides are released at synapses on
neurons involved in transmitting pain signals
to the brain
Opiate receptors
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When enkephalins bind to the opiate
receptors they inhibit neurons from
transmitting pain signal - pain signal does not
reach brain
Inhibit release of neurotransmitter
“Substance P”
Substance P used by the sensory neurons
involved in the perception of chronic and/or
intense pain
Opiate receptors
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Peptides and receptors form a complex
neurotransmitter system that plays a
major role in controlling pain, euphoria,
and motivation
Also involved in other biological events stress responses, immune regulation,
respiration, endocrine responses
Different classes of opiate receptors
Opiate receptors
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Three (or 4) classes of opiate receptors - with
subtypes of each
Opioids exert their effects by activating one
or more of these receptors
Pain relief involves activation of one type
receptors in the brain and another in the
spinal cord
Other receptors are are involved in
respiratory depression and euphoria
Opiate receptors
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m (mu) receptors - analgesia, euphoria
k (kappa) receptors - sedation, spinal
cord analgesia
d (delta) receptors - Antitussive
(coughing) properties, emesis
(vomiting), and anticholinergic
(constipation)
sigma (?) receptors cardiac stimulation
Opiates
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Morphine and the other opiates bind
these same receptors
Morphine especially binds to m receptors
Explains why opiates are excellent pain
killers
However, they are also highly addictive