Download S14 Cannabis

Cannabis
Cannabis
The use of marijuana for
medicinal proposes
dates back more then
5ooo years.
‫الحشاشون‬
‫•‬
‫طائفة إسماعيلية‪ ،‬انشقت عن الفاطميين‪ .‬أسسها الحسن‬
‫ً‬
‫مركزا‬
‫بن الصباح الذي اتخذ من قلعة آلموت في فارس‬
‫لنشر دعوته وترسيخ أركان دولته‪ .‬وقد تميزت هذه الطائفة‬
‫باحتراف القتل واالغتيال ألهداف سياسية ودينية متعصبة‪.‬‬
‫وكلمة الحشاشين‪ Assassin :‬دخلت بأشكال مختلفة في‬
‫االستخدام األوروبي بمعنى القتل خلسة أو غدرا ً أو بمعنى‬
‫القاتل المحترف المأجور‪.‬‬
Cannabis spp.
Cannabis is native to South Asia, where it was first
cultivated and developed into the two varieties.
It is now a cultivated crop and an invasive in
many parts of the world.
There are three species known:
Cannabis sativa, C. indica and C. rudelaris
The leaves are the most recognisable and wellknown aspect of the cannabis plant. Despite
the great degree of variation found naturally in
local populations of cannabis, the leaves do not
alter greatly in appearance between varieties .
What is Marijuana?
Marijuana is the dried mix
of flowers and leaves
form the female
Cannabis Sativa plant.
Hashish is the resin, or
sap, harvested from the
plant.
Hashish oil is the essential
oil of the female
Cannabis Sativa plant.
Cannabis Biology
Major Drug Component – delta-trans-tetrahydrocannabinol (THC)
- binds to specific receptors in brain
THC- produced in glands on leaves and flowers
-- female plants produce more glands
-- gland production stimulated by heat, sunlight, drought
-- sinsemilla (sin = without semilla = seeds) – particularly strong
Hashish – product - relatively pure resin
Glands
THC
Tetrahydrocannabinol (THC)
Tetrahydrocannabinol (THC) is the main psychoactive substance
found in the hemp plant Cannabis sativa, or marijuana.
Modes of Absorption
• The most common method of absorption is smoking. Either in
a loosely rolled cigarette called a joint, or through a pipe or
water pipe.
Smoking and the Body
THC enters the body through the Lungs.
The smoke is inhaled and held in the lungs.
All affect how much THC will enter the
plasma
THC crosses the blood barrier through the
capillaries in the lungs
After inhalation THC can reach the brain in
about 14 seconds
THC Effects
Along with euphoria, relaxation is another frequently reported effect in human
studies. Other effects, which vary dramatically from person to person, include
heightened sensory perception (e.g., brighter colors), laughter, altered
perception of time, and increased appetite. After a while, the euphoria subsides,
and the user may feel sleepy or depressed. In some users, marijuana can produce
anxiety, fear, distrust, or panic.
Marijuana users who have taken large doses of the drug may experience an acute
psychosis, which includes hallucinations, delusions, and a loss of the sense of
personal identity. Although the specific causes of these symptoms remain
unknown, they appear to occur more frequently when a high dose of cannabis is
consumed in food or drink rather than smoked.
The connection between marijuana use and cardiovascular risk could be partly
explained by marijuana’s ability to increase heart rate (and blood pressure—at
least initially) and reduce the blood's capacity to carry oxygen.
Cont…
Marijuana use impairs a person's ability to form new memories and to shift
focus, which can be particularly disruptive to young people, who are at a
stage in their lives when they should be absorbing critical information
and skills needed to realize their full potential.
THC also disrupts coordination and balance by affecting information
processing in the cerebellum and basal ganglia—parts of the brain that
regulate balance, posture, coordination, and reaction time. Therefore,
learning, doing complicated tasks, participating in athletics, and driving
are also affected. Not surprisingly, because marijuana impairs judgment
and motor coordination and slows reaction time, an intoxicated person
has an increased chance of being involved in and being responsible for
an accident. And in fact, a recent systematic review of nine independent
studies concluded that acute marijuana consumption is associated with
a doubling of the risk of a motor vehicle crash, especially of fatal
collisions.
Cannabinoids
Type-1 cannabinoid receptors (CB1) are
found in CNS
Stimulation of these receptors has analgesic
and anticonvulsant effects as well as
antiemetic/antinausea effects
The Cannabis High Described
Gives sensation of euphoria, relaxation, sexual
arousal•
1sttime users may experience nothing (experts say
they must learn to appreciate the effects)
•Marijuana tends to inhibit aggression and
accentuate caution as opposed to alcohol•
Marijuana causes time expansion (over estimation
of time elapsed)•
Workers say that smoking marijuana help them to
work harder
Marijuana smoke can have harmful effects on the heart
.
􀂾increased cardiac oxygen consumption􀂾
Reduced blood flow in coronary arteries􀂾
Increased carboxy-haemoglobin levels,
reducing the capacity of the blood to carry
oxygen􀂾
negative overall impact on atherosclerotic
heart disease.
Cannabinoids
• Cannabinoids are a group of chemicals
which activate the body’s cannabinoid
receptors. Before other types were
discovered, the term referred to a unique
group of secondary metabolites found in
the Cannabis plant and now sometimes
termed phytocannabinoids, which are
responsible for the plant's peculiar
pharmacological effects.
Cannabinoids
There are three general types of
cannabinoids:
􀂾endogenous cannabinoids produced in the
bodies of humans and other animals
􀂾herbal cannabinoids present in the
Cannabis plant
􀂾synthetic cannabinoids similar compounds
produced in a laboratory
Cannabinoid Receptors
Beforethe 1980s, it was often speculated that
cannabinoids produced their effects through non
specific interaction with cell membranes, instead
of interacting with specific receptors.
The discovery of the first cannabinoid receptors in
the 1980s helped to resolve this debate. These
receptors are common in animals, and have
been found in mammals, birds, fishes, and
reptiles.
There are currently two known types of
cannabinoid receptors, CB1 and CB2.
CB1 Receptors
Found primarily in the brain (specifically basal ganglia, limbic
system, including the hippocampus, and cerebellum)
􀂾Most dense in brain regions involved with thinking and memory,
attention and control of movement􀂾
Also present in both male and female reproductive systems as
well as in the lungs, liver and kidneys
􀂾Appear to be responsible for the euphoric and anticonvulsive
effects of Cannabis
􀂾Essentially absent in the medulla oblongata, the part of the brain
that is responsible for respiratory and cardiovascular
functions.
Thus, there is no risk of respiratory or cardiovascular failure as
there is with many other drugs.
CB2 Receptor
CB2 receptors are almost exclusively found in
the immune system (T cells, macrophages, B
cells), with the greatest density in the spleen
􀂾CB2 receptors appear to be responsible for
the anti-inflammatory and possible other
therapeutic effects of Cannabis
􀂾Also expressed on peripheral nerve terminals
Endocannabinoids
Both Δ9-THC, the
psychoactive
component of Cannabis
sativa, and anandamide,
an endogenous
neurotransmitter in our
brain, bind o the same
cannabinoid receptor
Drugs Can be Chemical Imposters
(THC mimics a natural brain chemical)
Brain’s Chemical
Drug
Anandamide
THC
Withdrawal Symptoms
Marijuana addiction is also linked to a
withdrawal syndrome that can make it
hard to quit. Symptoms include:
•
•
•
•
•
irritability,
sleeping difficulties,
craving,
anxiety, and
increased aggression.
Warning
Marijuana is illegal in most places
Marijuana is, in general, much less dangerous
than it is made out to be, and certainly less
harmful than legal drugs like tobacco and
alcohol.
It is impossible die from marijuana, unlike most
other illegal drugs and many legal ones.
Most of the supposed scientific evidence for brain
damage, infertility, etc. have been disproven.