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Introduction to How Marijuana Works
Marijuana is the buds and leaves of the Cannabis sativa plant. This plant contains more than 400 chemicals, including delta-9-tetrahydrocannabinol (THC), the plant’s main psychoactive chemical. THC is known to affect our brain’s short-term memory. Additionally, marijuana affects motor coordination, increases your heart rate and raises levels of anxiety. Studies also show that marijuana contains cancer-causing chemicals typically associated with cigarettes.
Marijuana plants contain more than 400 chemicals, 60 of which fit into a category called cannabinoids. THC is just one of these cannabinoids, but it’s the chemical most often associated with the effects that marijuana has on the brain. Cannabis plants also contain choline, eugenol, guaicacol and piperidine. The concentration of THC and other cannabinoids varies depending on growing conditions, plant genetics and processing after harvest.
Marijuana in the Body
Every time a user smokes a marijuana cigarette or ingests marijuana in some other form, THC and other chemicals enter the user’s body. The chemicals make their way through the bloodstream to the brain and then to the rest of the body. The most powerful chemical in marijuana is THC (delta-9-tetrahydrocannabinol), which is primarily responsible for the “high” associated with the drug.
The most common way of using marijuana is smoking. Smoking is also the most expedient way to get the THC and other chemicals into the bloodstream. When the smoke from marijuana is inhaled, the THC goes directly to the lungs. Your lungs are lined with millions of alveoli, the tiny air sacs where gas exchange occurs. These alveoli have an enormous surface area — 90 times greater than that of your skin — so they make it easy for THC and other compounds to enter the body. The smoke is absorbed by the lungs just seconds after inhaling.
You can also eat marijuana. In this case, the marijuana enters the stomach and the blood absorbs it there. The blood then carries it to the liver and the rest of the body. The stomach absorbs THC more slowly than the lungs. When marijuana is eaten, the levels of THC in the body are lower, but the effects last longer
Marijuana and the Brain
THC is a very potent chemical compared to other psychoactive drugs. An intravenous (IV) dose of only 1 milligram can produce serious mental and psychological effects. Once in your bloodstream, THC typically reaches the brain within seconds after it is inhaled and begins to go to work.
Marijuana users often describe the experience of smoking marijuana as initially relaxing and mellow, creating a feeling of haziness and light-headedness. The user’s eyes may dilate, causing colors to appear more intense, and other senses may be enhanced. Later, feelings of a paranoia and panic may be felt by the user. The interaction of the THC with the brain is what causes these feelings. To understand how marijuana affects the brain, you need to know about the parts of the brain that are affected by THC. Here are the basics:
- Neurons are the cells that process information in the brain. Chemicals called neurotransmitters allow neurons to communicate with each other.
- Neurotransmitters fill the gap, or synapse, between two neurons and bind to protein receptors, which enable various functions and allow the brain and body to be turned on and off.
- Some neurons have thousands of receptors that are specific to particular neurotransmitters.
- Foreign chemicals, like THC, can mimic or block actions of neurotransmitters and interfere with normal functions.
In your brain, there are groups of cannabinoid receptors concentrated in several different places. These cannabinoid receptors have an effect on several mental and physical activities, including:
- Short-term memory
- Coordination
- Learning
- Problem solving
Cannabinoid receptors are activated by a neurotransmitter called anandamide. Anandamide belongs to a group of chemicals called cannabinoids. THC is also a cannabinoid chemical. THC mimics the actions of anandamide, meaning that THC binds with cannabinoid receptors and activates neurons, which causes adverse effects on the mind and body.
High concentrations of cannabinoid receptors exist in the hippocampus, cerebellum and basal ganglia. The hippocampus is located within the temporal lobe and is important for short-term memory. When the THC binds with the cannabinoid receptors inside the hippocampus, it interferes with the recollection of recent events. THC also affects coordination, which is controlled by the cerebellum. The basal ganglia controls unconscious muscle movements, which is another reason why motor coordination is impaired when under the influence of marijuana.
The “Munchies”
One peculiar phenomenon associated with marijuana use is the increased hunger that users feel, often called the “munchies.” Research shows that marijuana increases food enjoyment and the number of times a person eats each day.
Until recently, the munchies were a relative mystery. However, a recent study by Italian scientists may explain what happens to increase appetite in marijuana users. Molecules called endocannabinoids bind with receptors in the brain and activate hunger.
This research indicates that endocannabinoids in the hypothalamus of the brain activate cannabinoid receptors that are responsible for maintaining food intake.
Other Physiological Effects of Marijuana
In addition to the brain, the side effects of marijuana reach many other parts of the body, which include:
- Problems with memory and learning
- Distorted perception
- Difficulty with thinking and problem solving
- Loss of coordination
- Increased heart rate
- Anxiety, paranoia and panic attacks
The initial effects created by the THC in marijuana wear off after an hour or two, but the chemicals stay in your body for much longer. The terminal half-life of THC is from about 20 hours to 10 days, depending on the amount and potency of the marijuana used. This means that if you take one milligram of THC that has a half-life of 20 hours, you will still have 0.031 mg of THC in your body more than four days later. The longer the half-life, the longer the THC lingers in your body.
The debate over the addictive capacity of marijuana continues. Ongoing studies now show a number of possible symptoms associated with the cessation of marijuana use. These symptoms most commonly include irritability, nervousness, depression, anxiety and even anger. Other symptoms are restlessness, severe changes in appetite, violent outbursts, interrupted sleep or insomnia. In addition to these possible physical effects, psychological dependence usually develops because a person’s mind craves the high that it gets when using the drug.
Beyond these effects that marijuana has, marijuana smokers are susceptible to the same health problems as tobacco smokers, such as bronchitis, emphysema and bronchial asthma. Other effects include dry mouth, red eyes, impaired motor skills and impaired concentration. Long-term use of the drug can increase the risk of damaging the lungs and reproductive system, according to the U.S. Drug Enforcement Agency (DEA). It has also been linked to heart attacks.
Although marijuana is known to have negative effects on the human body, there is a raging debate over the use of medicinal marijuana. Some say that marijuana should be legalized for medical use because it has been known to suppress nausea, relieve eye pressure, decrease muscle spasms, stimulate appetite, stop convulsions and eliminate menstrual pain. Because of its therapeutic nature, marijuana has been used in the treatment of several conditions including: cancer and AIDS (to supress nausea and stimulate appetite), glaucoma (to alleviate eye pressure), epilepsy (to stop convulsions) and multiple sclerosis (to decrease muscle spasms).
Source: HowStuffWorks
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“It is common for koalas to roam back to their home range afterwards and become confused to find nothing there. A worker noticed a koala had been sitting stationary in broad daylight on top of wood piles for over an hour.”
:’(
(Source: speakerforthetrees, via rockyourcasba)
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I highly endorse the proper and responsible use of LSD. I’ve had the most profound thoughts and self-discovery using acid.
SAME
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(Source: hardcoregurlz, via nutopiancitizen)
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click the + to gain more followers
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Scientists can now turn brains invisible
Say hello to the stunning results of CLARITY — a new technique that enables scientists to turn brain matter and other tissues completely transparent. It’s already being hailed as one of the most important advances for neuroanatomy in decades, and it’s not hard to see why.
Cut off a mouse’s head. Carefully remove its brain, wash it gently, and you’ll wind up with something resembling the sample pictured above, on the left. Grey matter, it so happens, lives up to its name. Due in large part to molecules known as lipids, organs like the brain are usually opaque. Lipids comprise cell membranes and provide structural support to a variety of organs and tissues throughout the body – but they also scatter light. As a result, most microscopes are lucky if they can peer even a millimeter into biological matter before images in the viewfinder get blurry.
One of the more popular techniques scientists use to get around this hangup is called “sectioning.” It’s brutally straightforward in practice: a researcher will freeze a chunk of tissue (a mouse brain, for example) in liquid nitrogen, and then slice it into scores of little sheets, each one just a fraction of a millimeter thick. This turns a single 3-dimensional problem (otherwise inscrutable, due to its non-transparent nature) into a series of 2-dimensional ones. Go through a brain layer by layer, and you can cobble together a volumetric picture of everything from cellular structure, to the spatial distribution of proteins, to the various connections that form between neurons. But the tradeoff is substantial. You’re literally cutting your sample into a bunch of tiny little pieces. With every slice, tissue is deformed, connections are severed, information is lost.
CLARITY does away with the slicing and dicing entirely. The technique, described in the latest issue of Nature by a team led by Stanford researchers Kwanghun Chung and Karl Deisseroth, works by stripping away all of a tissue’s light-scattering lipids, while leaving everything else right where it belongs. You’ll recall, however, that lipids play an important structural role in organs like the brain; if you remove them, everything else falls apart — a fact that has plagued past attempts at making tissues see-through. But that’s where CLARITY is different.
CLARITY works by virtue of a bait and switch. In their study, Chung and Deisseroth submerge a mouse brain in a mixture of formaldehyde and acrylamide. The former attaches important cellular structures and components to the latter, which solidifies into a gel when heated. An electrical current is then coursed through the gel, stripping it of anything not hanging on. The lipids go bye-bye, and the brain goes clear as Jell-O. More importantly: all of its significant structures remain intact and in place. Neurons, synapses, proteins, DNA. Every last component is exactly where it should be.
The ability to strip a brain of its lipids and nothing else gives rise to remarkable research possibilities. In the image above, a mouse brain turned transparent with CLARITY has been made visible again by labeling specific neurons with a fluorescent marker that glows green. Researchers have been using this technique (called “immunolabeling”) to highlight certain molecular and structural features for years, but with CLARITY, labeled cells can be seen in three dimensions, all at once.
In fact, the process of removing the brain’s lipids actually makes the tissues more permeable, making it easier to not only tag them with fluorescent markers in the first place, but untagthem and then tag them again with an entirely different label. What’s more, the fact that you don’t have to cut a brain up to see how it was stained means that you can add more tags to the same brain. The picture below shows a region of the brain known as the hippocampus that has had its different neurons labeled in a variety of fluorescent colors. A brain that was once impermeable to light has been made invisible, only to be made visible again – but this time with remarkable specificity.
There’s nothing that says this technique couldn’t be used on human brains, so long as you have the time. Coloring-in a clarified brain like the one above requires soaking it in solution with the fluorescent labels you want to tag it with. For a mouse brain, that can take a month or more. For a brain as voluminous as a human’s, it would take much longer. (While Chung and Deisseroth did demonstrate their technique could be used on human brains, they did so with a small block of tissue, not an entire brain.)
Likewise, there’s nothing that says CLARITY could not be used on tissues besides the brain, though the organ certainly shows the most immediate promise. The ability to visualize the neuronal connections throughout a transparent brain, for example, could spur incredible growth in the field of connectomics, which seeks to map the brain’s neuronal wiring. In neuroscience, few tools are as coveted as those that enable you to see the part and the whole simultaneously – CLARITY could enable researchers to study the structure and distribution of individual neurons in the context of the whole brain. “This is the kind of innovation that will slingshot neuroscience far beyond today,” said Henry Markram, leader of Europe’s recently unveiled Human Brain Project, in an interview with NatGeo’s Ed Yong. “This new method of whole-brain imaging across all levels of the brain provides a way to acquire much of the key data we will need.”
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Check out my indestructible 20$ pipe, yo
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On April 11 at 8:30 UTC, an M6 class solar flare occurred on the Sun. It produced a CME that is projected to reach the Earth on April 13th. It will cause a geomagnetic storm and aurora should be visible at lower latitudes. The best way to monitor the location of aurora is with the realtime NOAA Aurora Map. You can get precise weather predictions for your location with the ClearDarkSky Astronomy forecast. Seeing the aurora can be a life changing experience, good luck!
(via hackr)
