Drug could stop marijuana cravings

by Marcia Malory report

(Medical Xpress)—In the US, more people seek treatment for marijuana abuse than for abuse of cocaine or heroin. However, there are no approved treatments for marijuana addiction. Robert Schwarcz of the University of Maryland School of Medicine and his colleagues, including a group from the National Institute on Drug Abuse, have found a drug that appears to decrease the pleasurable effects of THC, marijuana's active ingredient, and could therefore prevent a psychological addiction to marijuana. The research appears in Nature Neuroscience.

THC produces a feeling of pleasure by increasing levels in the (VTA) and the shell of the nucleus accumbens (NAc). The researchers reasoned that if users took a that reduced dopamine activity in those regions of the brain, they would no longer experience a sense of euphoria when taking marijuana. Therefore, their marijuana usage would decrease.

Schwarz and his team gave rats the drug Ro 61-8048, which increases the brain's level of kynurenic acid (KYNA), a byproduct of the breakdown of tryptophan, an amino acid found in turkey and other foods. The researchers found that Ro 61-8048 increased levels of KYNA in the VTA and NAc shell and reduced the ability of THC or WIN 55,212-2, a synthetic THC substitute, to stimulate dopamine production in these regions. KYNA appears to block dopamine receptors.

The team then taught rats to give themselves WIN 55,212-2 by pressing a lever. The rats pressed the lever frequently, a sign of addiction. When the researchers gave the rats Ro 61-8048, lever-pressing subsided. To test whether Ro 61-8048 could prevent a relapse, the researchers trained rats to self-administer WIN 55,212-2 and then stopped providing it after a while. Lever-pressing decreased significantly until the rats were given WIN 55,212-2 injections. Then, frequent lever-pressing resumed. However, when the team gave rats Ro 61-8048, this relapse behavior did not occur. The team achieved similar results with squirrel monkeys trained to press a lever to obtain THC.

Schwarcz and his colleagues concede that scientists must do further research before the FDA can approve Ro 61-8048 or similar drugs for use in humans. High levels of KYNA are associated with cognitive defects, so the treatment could be worse than the cure. Proponents of marijuana decriminalization would argue that frequent use of marijuana is not necessarily a problem requiring treatment. The large number of people seeking help for marijuana addiction could reflect the fact that the law requires people arrested for drug crimes to seek such help.

More information: Reducing cannabinoid abuse and preventing relapse by enhancing endogenous brain levels of kynurenic acid, Nature Neuroscience (2013) doi:10.1038/nn.3540 www.nature.com/neuro/journal/vaop/ncurrent/full/nn.3540.html

Abstract
In the reward circuitry of the brain, α-7-nicotinic acetylcholine receptors (α7nAChRs) modulate effects of Δ9-tetrahydrocannabinol (THC), marijuana's main psychoactive ingredient. Kynurenic acid (KYNA) is an endogenous negative allosteric modulator of α7nAChRs. Here we report that the kynurenine 3-monooxygenase (KMO) inhibitor Ro 61-8048 increases brain KYNA levels and attenuates cannabinoid-induced increases in extracellular dopamine in reward-related brain areas. In the self-administration model of drug abuse, Ro 61-8048 reduced the rewarding effects of THC and the synthetic cannabinoid WIN 55,212-2 in squirrel monkeys and rats, respectively, and it also prevented relapse to drug-seeking induced by reexposure to cannabinoids or cannabinoid-associated cues. The effects of enhancing endogenous KYNA levels with Ro 61-8048 were prevented by positive allosteric modulators of α7nAChRs. Despite a clear need, there are no medications approved for treatment of marijuana dependence. Modulation of KYNA offers a pharmacological strategy for achieving abstinence from marijuana and preventing relapse.

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julianpenrod
1.3 / 5 (12) Oct 14, 2013
Those who wish to create a civilization in universal constant addiction say things like that marijuana does not affect brain cells, that it is only a mild soothing agent, like alcohol, and that it cannot cause addiction. Even the tangential side issues of this article seem in strict contradiction to those lies.
Also, notice the appeal to dull wittedness in promoting the subject of this article. It is being stated that Ro 61-8048 can "reduce dopamine activity" in those areas of the brain marijuana users seek to affect. This, supposedly will decrease their marijuana usage, because it would not longer be so pleasurable. But how would you get them to take the Ro 61-8048? Forcibly inject them, or dope up the dope? And if marijuana ceases to fulfill their admitted mindless pleasure seeking, they'll go to harder drugs!
WhyNotFeelGood
1.4 / 5 (11) Oct 14, 2013
Brilliant - now scientists want to make money on chemicals that make us feel like crap! (or at least limit our ability to feel good!) Geezuz Christ. It's an god-given herbal remedy used for millennium. Get over it. If it weren't for this narco-prison state, undoubtedly fewer people would be interested in using it. If you have an attention span longer than 5 minutes, I urge you to watch these 2 recent programs on the health benefits of cannabis...

http://www.youtub...nVEmdS2o (CNN)

https://www.youtu...9jc5EdDA (PBS)

Our bodies MAKE cannabinoids - and science is starting to realize that cannabis is a wonder drug for MANY conditions... not just because some people enjoy the soothing effects, but because of raw scientific facts.
WhyNotFeelGood
1 / 5 (10) Oct 14, 2013
Here's another example of druggies using "The Exit Drug".

http://abcnews.go...19720808
Roland
3.3 / 5 (3) Oct 14, 2013
"...more people seek treatment for marijuana abuse than for abuse of cocaine or heroin." This is because judges give some cannabis "offenders" a choice: "treatment" or jail. Cannabis is not addictive! No, I can't prove it, because you can't logically prove a negative. The onus is on the other side.
Shootist
1.4 / 5 (11) Oct 14, 2013
"...more people seek treatment for marijuana abuse than for abuse of cocaine or heroin." This is because judges give some cannabis "offenders" a choice: "treatment" or jail. Cannabis is not addictive! No, I can't prove it, because you can't logically prove a negative. The onus is on the other side.


Your observations equal mine are the same as mine. The WoD™ drives treatment modalities. Court ordered treatment is the major admittance vector.
megmaltese
1.4 / 5 (12) Oct 14, 2013
This substance makes people happy, let's produce another substance that inhibits those effects!

Or even better, let's try to find some substance that will ERADICATE definitively that dangerous happy-substance producer plant! (it will come, no worries)
cmn
5 / 5 (3) Oct 14, 2013
Anything that alters dopamine levels in the brain can be addictive, from comfort foods to caffeine to antidepressants. Although THC may not physically alter the brain, it definitely can be psychologically addictive if you become accustom to certain elevated dopamine levels. The ethical/pragmatic implications of this aren't really the point, as each person handles the plant differently. However, for those that society deems necessary of treatment (however flawed or righteous their reasons may be), this research shows that the 'cravings' can be 'negated' by this drug.
pauljpease
1 / 5 (2) Oct 14, 2013
@julianpenrod:

Talk about wanting to create a nanny state. It is every human's God given right to live their life as they see fit, so long as they don't hurt others. If you claim using relatively harmless drugs hurts others and therefore needs to be banned, then caffeine, alcohol, tobacco, etc. need to be banned as well. Especially alcohol, which has catastrophic consequences for society, from causing cancer to drunk driving deaths to violence. Just because some people weren't born with your perfect brain doesn't mean you should advocate restricting their access to something that helps them feel better.
PoppaJ
1.4 / 5 (11) Oct 14, 2013
The worst kind of politically driven crap ever. Robert Schwarcz is a psychologist and in no way qualified to make determinations or interpret data involving chemical processes in the brain. National Institute on Drug Abuse is a government body paid to do nothing more than prove the validity of there position. What has happened here is NIDA did a sham study to promote a drug they created that alters the chemicals in the human in the brain in a truly dangerous way and paid this crack pot to interpret it! Medical express should be ashamed of themselves for posting this garbage.
pauljpease
2 / 5 (5) Oct 14, 2013
@Shootist,

Cannabis IS addictive. I'm speaking from personal experience. Cessation causes withdrawal symptoms including nausea, anxiety and other symptoms that appear similar to mania. Don't know if it is addictive for everyone, and likely it is not. It's been shown that not everyone gets addicted to nicotine either, has to do with expression of specific receptors in the brain. They showed that the people who try smoking tobacco but never take up the habit and never get addicted have different expression of nicotine receptors. Obviously the same diversity would be found in the population for cannabinoid receptors.

I would also like to add that addiction to cannabis is relatively mild and I'm guessing the very real addiction many people get to sugar and fat is more harmful to their health and to society. So, cannabis addiction isn't a terrible plague on society, but it also is real.
RobertKarlStonjek
1.2 / 5 (6) Oct 14, 2013
Whenever an addict experiences a drop in response to a drug, a phenomena caused by increase tolerance to the drug, addicts typically seek more of the drug and/or stronger dosages.

Why do the researchers think that in the case of THC those addicted would respond in the opposite way to reduced effect?

Notably, addicts are more likely to seek relief from the rebound effect of the drug. If, for instance, you take a medication that relieves pain then stopping that drug may cause a spike in pain sensation, a 'rebound' effect. This is just one aspect of withdrawal symptoms that a person may suffer upon cessation of a drug (including some drugs prescribed by a doctor).

If researchers are assuming that the addiction is to the pleasurable effects then they are sadly mistaken. Pleasure may be the enticement that lures the unwary, but pleasure alone will not cause addiction.
Shootist
1.1 / 5 (11) Oct 14, 2013
@Shootist,

Cannabis IS addictive.


If you wish to claim to be addicted far be it from me to dissuade you.
jackii
1 / 5 (4) Oct 15, 2013
well of course they would come up with a contra-marijuana drug, it's a threat to the alcohol industry afterall. if they really wanted to produce a societally beneficial cure, then find a cure for alcohol addiction!
Wolf358
not rated yet Oct 15, 2013
From the article: The researchers reasoned that if marijuana users took a drug that reduced dopamine activity in those regions of the brain, they would no longer experience a sense of euphoria when taking marijuana. Therefore, their marijuana usage would decrease.
How stupid can you get? If you get used to smoking something to get a buzz, and you get less buzz (for whatever reason), you'll smoke _more_. Some "scientists" need to get out of the lab and go to a few parties... Sheesh! :-)
CrossEyedJack
1 / 5 (10) Oct 15, 2013
I can't speak for everyone. I've smoked MJ for more then 20 years. I've never had any cravings. Evan during times when I smoked heavy (More then a Gram a day). I wish I could same the same for cigarettes. Oh BTW I'm a Software Engineer and Graduated with a 3.67 GPA. Never once have I felt dull. Some of the smartest people I know are stoners. If anything I think it makes you smarter and more creative. I've smoked everything from Mexican Brick weed to Afgan blonde Hash. Personally I think its the FDA/Drug companies that keep it down. Cause it works better then there B.S. Pills. Only real harm is the Smoke and of course that not good for the lungs. If was Legal then you can make it other forms or vaporize it. Nothing but Lies and Propaganda.
Expiorer
1 / 5 (9) Oct 15, 2013
It is like saying - help me I can not stop eating chocolate .
No treatment for that as well.
(eating too much chocolate and candies kills teeth)
EnricM
1 / 5 (9) Oct 15, 2013
well of course they would come up with a contra-marijuana drug, it's a threat to the alcohol industry afterall. if they really wanted to produce a societally beneficial cure, then find a cure for alcohol addiction!


I got it! It's called hangover, LOL

cantdrive85
1 / 5 (8) Oct 15, 2013
Cannabinoids have been shown to kill cancerous cells, I'm on a preemptive regimen to prevent cancer. Ever since my step-father was diagnosed with bone cancer I have increased my dosage since there is a prevalence in my family.
Anonym
1 / 5 (8) Oct 15, 2013
Agree with most of you folks. It's not physically addicting, and it is only as psychologically addicting as any other pleasurable activity, such as watching TV, having a beer, or ANY other habit or ritual behavior.

Meanwhile, it also appears cannabis is an effective, broad-spectrum, non-toxic treatment for a wide range of medical conditions (linked to a deficiency of endocannabinoids in the body) including cancer, MS, and cerebral palsy. It has long been known cannabis effectively treats glaucoma.

In my experience, the only "withdrawal" symptom after long-term use is a day of mild queasiness. There is no "craving" at all.

It is supremely frustrating that my tax dollars go to support the corrupt anti-cannabis agenda of the drug, liquor and cigarette lobbies. SHAME on the cynical (or ignorant) politicians, government-controlled scientists, and hypocritical judges who have caused incalculable damage to our society.
Neinsense99
1 / 5 (4) Oct 19, 2013
The WoD™ drives treatment modalities. Court ordered treatment is the major admittance vector.

Let's declare war on gratuitous declarations of war. Throw anyone in jail who makes expensive, usually self-serving and typically wrong-headed declarations of war on this or that. In the absence of empty rhetoric, might something useful actually get done?