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Dr Sanjay Gupta's CNN Special "WEED"
CBD possesses sedative properties (Carlini and Cunha, 1981), and a clinical
trial showed that it reduces the anxiety and other unpleasant psychological
side effects provoked by pure THC (Zuardi et al. 1982). CBD modulates the
pharmacokinetics of THC by three mechanisms: (1) it has a slight affinity for
cannabinoid receptors (Ki at CB1 = 4350 nM, compared to THC = 41 nM,
Showalter et al. 1996), and it signals receptors as an antagonist or reverse agonist
(Petitet et al. 1998), (2) CBD may modulate signal transduction by perturbing
the fluidity of neuronal membranes, or by remodeling G-proteins that
carry intracellular signals downstream from cannabinoid receptors, and (3)CBD
is a potent inhibitor of cytochrome P450 3A11 metabolism, thus it blocks the
hydroxylation of THC to its 11-hydroxy metabolite (Bornheim et al. 1995).
The 11-hydroxy metabolite is four times more psychoactive than unmetabolized
THC (Browne and Weissman 1981), and four times more immunosuppressive
(Klein et al. 1987).
CBD provides antipsychotic benefits (Zuardi et al. 1995). It increases dopamine
activity, serves as a serotonin uptake inhibitor, and enhances norepinephrine
activity (Banerjee et al. 1975; Poddar and Dewey 1980). CBD protects
neurons from glutamate toxicity and serves as an antioxidant, more potently
than ascorbate and α-tocopherol (Hampson et al. 1998). Auspiciously, CBD
does not decrease acetylcholine (ACh) activity in the brain (Domino 1976;
Cheney et al. 1981). THC, in contrast, reduces hippocampal ACh release in
rats (Carta et al. 1998), and this correlates with loss of short-term memory consolidation.
In the hippocampus THC also inhibits N-methyl-D-aspartate (NMDA)
receptor activity (Misner and Sullivan 1999; Shen and Thayer 1999), and
NMDA synaptic transmission is crucial for memory consolidation (Shimizu et
al. 2000). CBD, unlike THC, does not dampen the firing of hippocampal cells
(Heyser et al. 1993) and does not disrupt learning (Brodkin and Moerschbaecher
1997).
Consroe (1998) presented an excellent review of CBD in neurological disorders.
In some studies, it ameliorates symptoms of Huntington’s disease, such
as dystonia and dyskinesia. CBD mitigates other dystonic conditions, such as
torticollis, in rat studies and uncontrolled human studies. CBD functions as an
anticonvulsant in rats, on a par with phenytoin (Dilantin, a standard antiepileptic
drug).
CBD demonstrated a synergistic benefit in the reduction of intestinal motility
in mice produced by THC (Anderson, Jackson, and Chesher 1974). This
may be an important component of observed benefits of cannabis in inflammatory
bowel diseases.
--"Cannabis and Cannabis Extracts:
Greater Than the Sum of Their Parts?
John M. McPartland
Ethan B. Russo"
Weed And Driving
^Wrong again, my friend. I never mentioned that I thought you were a marijuana user. I was referring to other comments made by... potheads. I'm sorry if you felt wrongly accused.
Do you need citations? Okay, here:
If you'd like more examples of how boneheaded this debate is, I will gladly throw a few together when I have 10 more minutes.
Sleep Loss = Brain Drain
Source:
Skaggs, WE & McNaughton, BL
(1996)
Replay of neuronal firing sequences
in rat hippocampus during sleep
following spatial experience
Science 271: 1870 - 1873
Final Part of Ted Kennedy's Eulogy for Bobby
One with such a gleaming track-record in senate speaks of moral courage...hear his tumor has had it's own hippocampus for years, and has produced enough neurons and dendritic activity to keep his head alive-plans to place it in a jar on the senate floor wired with an voice-interface are already under way.....
(choggie, you sick puppy)
Co-ordinated Kittens (Kinda)
I'd upvote only my doctor tells me I probably have a lesion across my hippocampus that needs immediate repair
Never Get Busted Again... Tips from an ex-cop
Talk out your arse much cobalt?
http://en.wikipedia.org/wiki/Health_issues_and_the_effects_of_cannabis
[edit] Toxicity
According to the Merck Index,[2] the LD50 (dosage lethal to 50% of rats tested) of Δ9-THC by inhalation is 42 mg/kg of body weight. That is the equivalent of a man weighing 75 kg (165 lb) inhaling the THC found in 21 grams of extremely high-potency (15% THC) marijuana all in one sitting, assuming no THC is lost through smoke loss or absorption by the lungs. For oral consumption, the LD50 for male rats is 1270 mg/kg, and 730 mg/kg for females—equivalent to the THC in about a pound of 15% THC marijuana.[3] The ratio of cannabis material required to saturate cannabinoid receptors to the amount required for a fatal overdose is 1:40,000.[4] There have been no reported deaths or permanent injuries sustained as a result of a marijuana overdose. It is practically impossible to overdose on marijuana, as the user would certainly either fall asleep or otherwise become incapacitated from the effects of the drug before being able to consume enough THC to be mortally toxic. According to a United Kingdom government report, using cannabis is less dangerous than tobacco, prescription drugs, and alcohol in social harms, physical harm and addiction.[5]
[edit] Confounding combination
The most obvious confounding factor in cannabis research is the prevalent usage of other recreational drugs, including alcohol and tobacco.[6] One paper claims marijuana use can increase risk of squamous cell carcinoma of the head and neck. [7] Such complications demonstrate the need for studies on cannabis that have stronger controls, and investigations into the symptoms of cannabis use that may also be caused by tobacco. Some people question whether the agencies that do the research try to make an honest effort to present an accurate, unbiased summary of the evidence, or whether they "cherry-pick" their data, and others caution that the raw data, and not the final conclusions, are what should be examined.[8]
However, contrasting studies have linked the smoking of cannabis to lung cancer and the growth of cancerous tumors.[9][10][11][12] A 2002 report by the British Lung Foundation estimated that three to four cannabis cigarettes a day were associated with the same amount of damage to the lungs as 20 or more tobacco cigarettes a day.[13] Some of these finding may be attributed to the well-known custom that many British citizens often mix tobacco with marijuana. It should also be noted that a recent study conducted at a lab in UCLA has found no link between marijuana usage and lung cancer.[citation needed]
Cannabis also has a synergistic toxic effect with the food additive Butylated hydroxyanisole (BHA) and possibly the related compound butylated hydroxytoluene (BHT). The study concluded, "Exposure to marijuana smoke in conjunction with BHA, a common food additive, may promote deleterious health effects in the lung." BHA & BHT are man-made fat preservatives, and are found in many packaged foods including: plastics in boxed Cereal, Jello, Slim Jims, and more. [14]
[edit] Memory
Cannabis is known to act on the hippocampus (an area of the brain associated with memory and learning), and impair short term memory and attention for the duration of its effects and in some cases for the next day[15]. In the long term, some studies point to enhancement of particular types of memory.[16] Cannabis was found to be neuroprotective against excitotoxicity and is therefore beneficial for the prevention of progressive degenerative diseases like Alzheimer's disease.[17] A 1998 report commissioned in France by Health Secretary of State Bernard Condevaux and directed by Dr. Pierre-Bernard Roques determined that, "former results suggesting anatomic changes in the brain of chronic cannabis users, measured by tomography, were not confirmed by the accurate modern neuro-imaging techniques," (like MRI). "Moreover, morphological impairment of the hippocampus [which plays a part in memory and navigation] of rat after administration of very high doses of THC (Langfield et al., 1988) was not shown (Slikker et al., 1992)" (translated). He concluded that cannabis does not have any neurotoxicity as defined in the report, unlike alcohol and cocaine.[18][19][20]
[edit] Adulterated cannabis
Contaminants may be found in hashish when consumed from soap bar-type sources[21]. The dried flowers of the plant may be contaminated by the plant taking up heavy metals and other toxins from its growing environment[22]. Recently, there have been reports of herbal cannabis being adulterated with minute (silica [usually glass or sand], or sugar} crystals in the UK and Ireland. These crystals resemble THC in appearance, yet are much heavier, and so serve again to increase the weight, and hence street value of the cannabis[23].
[edit] Pregnancy
Studies have found that children of marijuana-smoking mothers more frequently suffer from permanent cognitive deficits, concentration disorders, hyperactivity, and impaired social interactions than non-exposed children of the same age and social background.[24][25] A recent study with participation of scientists from Europe and the United States, have now identified that endogenous cannabinoids, molecules naturally produced by our brains and functionally similar to THC from cannabis, play unexpectedly significant roles in establishing how certain nerve cells connect to each other. The formation of connections among nerve cells occurs during a relatively short period in the fetal brain. The study tries to give a closer understanding of if and when cannabis damages the fetal brain[26][27].[28]
Other studies on Jamaica have suggested that cannabis use by expectant mothers does not appear to cause birth defects or developmental delays in their newborn children.[29][30] In a study in 1994 of Twenty-four Jamaican neonates exposed to marijuana prenatally and 20 non exposed neonates comparisons were made at 3 days and 1 month old, using the Brazelton Neonatal Assessment Scale, including supplementary items to capture possible subtle effects. Results showed there were no significant differences between exposed and nonexposed neonates on day 3. At 1 month, the exposed neonates showed better physiological stability and required less examiner facilitation to reach organized states. The neonates of heavy-marijuana-using mothers had better scores on autonomic stability, quality of alertness, irritability, and self-regulation and were judged to be more rewarding for caregivers. This work was supported by the March of Dimes Foundation.[31]
[edit] Cancer
On 23 May 2006, Donald Tashkin, M.D., Professor of Medicine at the David Geffen School of Medicine at UCLA in Los Angeles announced that the use of cannabis does not appear to increase the risk of developing lung cancer, or increase the risk of head and neck cancers, such as cancer of the tongue, mouth, throat, or esophagus.[32]The study involved 2252 participants, with some of the most chronic marijuana smokers having smoked over 22,000 marijuana cigarettes.[32][33][34][35] The finding of Donald Tashkin, M.D., and his team of researchers in 2006 refines their earlier studies published in a Dec. 17th 2000 edition of the peer-reviewed journal Cancer Epidemiology Biomarker and Prevention.[12] Many opponents of marijuana incorrectly cite the original finding of UCLA Medical Center from 2000 as "proof" that marijuana leaves the users at higher risk for cancer of the lung, and cancerous tumors,[9] even though the researchers at the UCLA Medical Center have revised their finding with a more in-depth study on the effects of the use of marijuana. This seemed to contradict assumptions made after some studies, like those from Dale Geirringer et al., which found that 118 carcinogens were produced when marijuana underwent combustion, and two carcinogens {2-Methyl-2, 4(2H-1-benzopyran-5-ol) & 5-[Acetyl benz[e]azulene-3,8-dione} formed when marijuana underwent vaporization with the Volcano Vaporizer.[36] To help explain this seemingly chemical proof of carcinogenity inherent in the process of combustion, Tashkin noted that "one possible explanation for the new findings, he said, is that THC, a chemical in marijuana smoke, may encourage aging cells to die earlier and therefore be less likely to undergo cancerous transformation."[32]
the parts of the brain (anatomy song by pinky & the brain)
"NOOOOW1? Yall' kin sang louder n' that!?, Here;s the words t' foller' aloooong!"
BRAINSTEM (Episode P3)
Lyrics by Tom Minton.
Sung to Camptown Races by Stephen Foster.
Pinky: And now, the parts of the brain, performed by The Brain!
Brain: Ye-e-s!
Brain: Neo-cortex, frontal lobe
Pinky: Brainstem! Brainstem!
Brain: Hippocampus, neural node
Right hemisphere.
Brain: Pons and cortex visual
Pinky: Brainstem! Brainstem!
Brain: Sylvian fissure, pineal
Left hemisphere.
Brain: Cerebellum left!
Cerebellum right!
Synapse, hypothalamus
Striatum, dendrite.
Brain: Axon fibers, matter gray
Pinky: Brainstem! Brainstem!
Brain: Central tegmental pathway
Temporal lobe.
Brain: White core matter, forebrain, skull
Pinky: Brainstem! Brainstem!
Brain: Central fissure, cord spinal
Parietal.
Brain: Pia mater!
Menengeal vein!
Medulla oblongata and lobe limbic
Micro-electrodes...
Pinky: Naaarf!
P+B : THE BRAIN!!!
Brain: That ought to keep the little squirts happy. Ye-e-s!