Posted on 12/27/2005 7:26:46 AM PST by billorites
Marijuana--or more specifically its active ingredient, tetrahydrocannabinol--has a well-documented tendency to stimulate hunger. And while scientists have traced this property to cannabinoid receptors in the brain, they have had little understanding of the neural circuitry underlying this effect.
Understanding this circuitry has important practical implications because blocking the cannabinoid receptor, CB1, offers a promising approach to treating obesity. One such compound, rimonabant (trade name AcompliaTM) is already undergoing clinical testing.
In an article in the December 22, 2005, issue of Neuron, Young-Hwan Jo and colleagues report how the circuitry of CB1 is integrated with signaling by the appetite-suppressing hormone leptin. The CB1 receptor is normally triggered by natural regulatory molecules, called endocannabinoids.
In their studies, the researchers concentrated on the lateral hypothalamus (LH) of the brain, known to be a center of control of food intake. Their studies involved detailed electrophysiological measurements of the effects of specific neurons that they had identified in previous studies as being important in endocannabinoid signaling.
Their studies revealed that activation of CB1 receptors, as by endocannabinoid molecules, induced these neurons to be rendered more excitable by a mechanism called "depolarization-induced suppression of inhibition" (DSI).
What's more, they found that leptin inhibits DSI. However, they found that leptin did not interfere with the CB1 receptors themselves. Rather, leptin "short-circuits" the endocannabinoid effects by inhibiting pore-like channels in the neurons that regulate the flow of calcium into the neurons. Such calcium is necessary for the synthesis of endocannabinoids.
In further studies of mice genetically altered to be leptin deficient, the researchers found the DSI to be more prolonged than in normal mice. Thus, they said, the findings "implicate this mechanism for leptin receptor/endocannabinoid signaling in contributing to the maintenance of weight balance...." The researchers also included that "upregulation of endocannabinoid signaling in the LH may explain, at least in part, the increased body weight consistent with a prior report of elevated endocannabinoids" in such leptin-deficient mice.
The researchers concluded that their findings "are consistent with the hypothesis that the integration of endocannabinoid and leptin signaling regulates the excitability of neurons on appetite-related circuits."
They also wrote that "the cellular mechanisms of recently developed antiobesity drugs, such as rimonabant, may include decreased endocannabinoid signaling and hence decreased excitability of LH circuits related to appetite, even in the context of leptin insufficiency or resistance."
I think they're barking up the wrong tree.
Psychedelic drugs, besides making colors seem brighter and prettier, also make food taste much better.
We now live in a world without eternal mysteries.
Did the subs we ordered get here? Check the trash can.
This is an important study. The munchies are a real phenomenon from marijuana. Stimulation of appetite would be a real help in many medical conditions, where malnutrition caused by a lack of appetite makes the condition worse.
Any of you who have elderly parents or grandparents know that it's tough to get them to eat properly or enough. A medication that stimulated the appetite would be a real boon to these folks and others who have diminished or non-existant appetites.
But, jokes about the munchies are also appropriate.
That medication already exists: it's called marijuana. (And if used from a vaporizer rather than smoked it doesn't have the ill effects of smoking.)
You make great points. But I'll bet the focus of any research will be on appetite suppression, not stimulation. That is because there is a HUGE market out there for an anti-obesity miracle drug.
How the heck does this work?
A common misconception. Marijuana has many active ingredients ... which is why the Canadian-approved medicine Sativex uses the whole plant rather than extracting a subset of its active ingredients.
>>>Psychedelic drugs, besides making colors seem brighter and prettier, also make food taste much better. >>>
I don't think Marijuana is a "Psychedelic" drug.
Depends. Sativa is more psyche than indica. Most of what is sold today is an indica hybrid. Back in the sixties, however...
>>>That medication already exists: it's called marijuana. >>>
Brilliant, and accurate. If people would get over the stigma of marijuana and all the propaganda of the early 20th century we could move on from the garbage and actually start using it for good. Whiskey, honey and lemon can do wonders for a chest cold, but that doesn't mean that drinking a fifth of whiskey a day is a good thing. Why can't people understand there is a medicinal value to something just because others abuse it? Hell, I know people that abuse cough syrup, that shouldn't be illegal.
In a free society nobody needs to "justify" any non-rights-violating act.
A close friend of mine, who has anorexia severe enough to inhibit her reproductive organs, would benefit enormously from an appetite-stimulating drug that didn't carry the deleterious effects that pure marijuana has.
Already exists. Called Marinol. Here's the product info:
Product Information
MARINOL® is a unique prescription medicine that relieves multiple symptoms. The United States Food and Drug Administration (FDA) approved MARINOL® to treat nausea and vomiting associated with cancer chemotherapy in patients who have failed to respond adequately to conventional treatments.
The FDA also approved MARINOL® to treat appetite loss associated with weight loss in people with AIDS. Health care professionals may prescribe MARINOL® to help stimulate an HIV/AIDS patient’s appetite so he or she will want to eat again.
MARINOL® is a synthetic version of a naturally occurring compound known as delta-9-THC. Delta-9-THC stimulates appetite and reduces nausea and vomiting by binding to special receptors found in the nervous system.
MARINOL® is contraindicated in any patient who has a history of hypersensitivity to any cannabinoid or sesame oil.
Patients should be warned not to drive, operate machinery, or engage in hazardous activity until they establish they can tolerate MARINOL® and perform such tasks safely.
A cannabinoid dose-related “high” (easy laughing, elation and heightened awareness) has been reported by patients receiving MARINOL® in both the antiemetic (24%) and the lower dose appetite stimulant clinical trials (8%). Other frequently reported adverse events in MARINOL® clinical trials included abdominal pain, nausea, vomiting, dizziness, euphoria, paranoid reaction, somnolence, and thinking abnormal.
I'll give you a Libertarian justification for smoking: if I smoke it, it's none of your business. How's that?
>>>In a free society nobody needs to "justify" any non-rights-violating act.>>>
I get so sick of people dismissing the medicinal uses of marijuana. My mother, a Christian and Sunday School teacher, used marijuana in her last months with cancer. With abdominal cancer, nausea is a bigger problem than pain and she was getting dehydrated and couldn't even keep water or popsicles down. They said the dehydration would kill her before the cancer and she didn't want to think of months in a hospital hooked up to IV's, wanted to be at home. I mentioned to her that people with cancer don't smoke cause it's a party, they smoke because it helps. So she agreed and then she thanked God he put it on this earth for her use. It didn't save her life, but it sure helped her tolerate her time here and didn't force her to go into a coma (to help with the nausea, which was the other alternative, because the nausea medicines are so strong nad knock you out) so she could spend time with me and her grandkids and husband. Some people are so stupid and selfish about denying others their RIGHT to use a substance grown freely, that they would rather see a grandmother lose precious moments with loved ones being in a 'LEGAL' coma from 'LEGAL' DRUGS rather than use what God gave us.
This is a touchy subject for me, can you tell?
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