Some new findings on Nicotine Addiction

Joined: 18 Dec 2008, 23:57

15 Mar 2002, 06:40 #21

Ingrid, don't you remember the aaaahhhhhhh feeling that arrived within 8 to 10 seconds of a new puff? An almost constant dopamine output was our new sense of normal. Did you go an hour without a new fix? Not this kid! About every 15 minutes I was tanking up again! I was Mayor of Dopamineville! The lure that captured each of us was the unaddicted aaaaahhhhhh sensation but once captive, it was no longer a matter of choice but of necessity. My captive aaaaahhhhhs were the feeling of raising my falling blood serum nicotine level so that I didn't have to keep sensing the signs of early withdrawal that I knew were always just around the corner. Some of Joel's articles talk about the "Perfect Smoke" but for me the best one was always the first one each day after going the whole night without a fix or maybe after a meal where I had not been able to smoke for the better part of an hour.
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Joined: 18 Dec 2008, 23:58

15 Mar 2002, 06:50 #22

I guess I smoked too constantly to allow myself to get anywhere 'needing' a fix! However there were times when I couldn't have one for a period of time that I do remember that aaaaahhhhhh sensation. As far as that first one in the morning...well I was too busy coughing to be aware that it was pleasurable! I don't cough at all now by the way - the human body has a wonderful recovery mechanism!!
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Joined: 19 Dec 2008, 00:29

15 Mar 2002, 07:28 #23

Right on Brother John!! And very cool "syapse" gif to boot!

Thanks again for your patience Joel, and for answering even more of the endless questions! OK, let me see if I get this...the reason I smoked more during times of "elation" was to possibly arrest the acetylcholine thus insuring continued dopamine release? Very clever that nicotine, double dipping in the pleasure centers! Well, I do think my dopamine has returned to normal and there is so much pleasure in life without the torture of nicotine addiction. Just fearful of the damage I've already done, ironic isn't it? I killed myself daily by smoking without a thought, now that's behind me...I start to worry about the damage done! I can't go back in time, I can only continue to gain more education and of course Never Take Another Puff!!

*Candy* 4months
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Joined: 18 Dec 2008, 23:59

15 Mar 2002, 22:28 #24

I can't let this post rest and slide to the bottom. I love reading what everyone is saying about how controlling nicotine is and how it once controlled us. It's so true. Keep posting. And we'll all learn alot about it's addictive-ness. Is that a word?
Thanks. I love this new information on dopamine and what Grumpy said too about the dual effect - - desire/repulsion, mind controlling, a real nasty drug.
OK
Have another great nicotine free day of FREEDOM
YQS
Alice
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Joined: 09 Jan 2009, 00:32

03 Apr 2002, 14:38 #25

Thanks, Joel. Very informative.

I can't believe the endless power of this "beast."

(e.g., " ...they may have smoked to celebrate not so much to just pour in more dopamine, but rather to inactivate acetylcholine making the thrill of the accomplishment last longer...")

This is ALL making so much sense to me now....

Thanks for the education. I feel like I'm being armed for battle. And I'm grateful.

Laura
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Joined: 18 Dec 2008, 23:57

19 May 2002, 05:41 #26

Just want to make sure that everyone here keeps a full appreciation of what they are fighting. Cigarette smoking is a drug addiction--pure and simple--and as can be seen by this research, one of the most efficiently devised and powerful drug delivery systems ever developed by man. To avoid ever being trapped in nicotine's grip again always remember to never take another puff!

Joel
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Joined: 18 Dec 2008, 23:57

07 Jun 2002, 20:42 #27

One more for Dos. Doesn't explain why you took the first one but it sure gives some insight to what caused the tens or hundreds of thousands that followed. The way to stop the future tens or hundreds of thousands now is simply knowing to never take another puff!

Joel
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Joined: 18 Dec 2008, 23:57

30 Aug 2002, 05:25 #28

Whether it was the first cigarette you ever smoked, the second, the twentieth or the hundreth--one of them finally took you over the edge and addicted you. That addiction is going to be with you the rest of your life now. It will become asymptomatic--there will be no visible or obvious signs or manifestations letting you or anyone else know it is there--but it is still there. Whether the first one you ever smoked hooked you or not, the next one will reestablish your need for nicotine and will be a in every sense of the word a relapse to a potentially life threatening active drug addiction. To avoid ever being trapped in nicotine's grip again is as simple though as knowing now to never take another puff!

Joel

How long does it take to become addicted?
That first puff is a real doozy
Was I addicted?
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Joined: 07 Jan 2009, 19:23

04 Oct 2002, 23:19 #29

Just like what the heroin does: tampering with the chemicals in the brain. Numbing pain and mind. When you tamper with that by manually providing the brain with more, the brain shuts down it's creation process knowing it has plenty on hand. Then when you try to stop doing the junk, withdrawal sets in because it takes the brain a few days to generate the chemicals that it had an abundance of.

Peachy - I guess the same goes with nicotine. The withdrawal makes us grumpy enough to become vicious and/or violent.
Frank
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Joined: 18 Dec 2008, 23:57

09 Dec 2002, 20:57 #30

Just want to make sure that everyone here keeps a full appreciation of what they are fighting. Cigarette smoking is a drug addiction--pure and simple--and as can be seen by this research, one of the most efficiently devised and powerful drug delivery systems ever developed by man. To avoid ever being trapped in nicotine's grip again always remember to never take another puff!

Joel
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Joined: 09 Jan 2009, 20:39

09 Dec 2002, 21:47 #31

Hi Joel, Thanks for that useful info. I came here this morning because I have been feeling so low the last couple of days (I'm on day 14 nicotine free). I was telling someone the other day that I don't know how to be happy without my nicotine. It's as though I forgot HOW to be happy. After reading the Trib article, I can see why I said that. I have had some positive experiences since I quit - but my lows seems so much lower now that I'm not using that nasty drug. The article helped me to keep things in perspective, and realize that THIS IS ONLY TEMPORARY! I'll continue taking it one day at a time, and remember cigarettes for what they are - a highly addictive drug delivery system! Thanks again!
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Joined: 18 Dec 2008, 23:57

09 Dec 2002, 21:57 #32

Here Marie, be sure to read this one too:
Emotional Loss Experienced from Quitting Smoking
Last edited by Joel on 10 Jul 2009, 16:46, edited 1 time in total.
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Joined: 19 Dec 2008, 00:00

23 Dec 2002, 12:10 #33

for Jill.....not sure if this is the one you wanted, but there are links to other threads about dopomine levels in here.

Linda
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Joined: 07 Jan 2009, 19:05

03 Feb 2003, 23:01 #34

Wow, Joel, I knew I was addicted, but never realized how powerful a drug nicotine is. Thanks for sharing this article. It just reinforces why I never want to take another puff, who wants to go through the pain of withdrawal ever again!

I also think this article points out some other things that you've taught us. For instance, how other problems "suddenly" appear when we quit smoking. Most have been covered up with all that dopamine all the years we smoked. I'm not a big proponent of main stream medicine, but I must say that there are plenty of medications and other therepies available now to help overcome the "new" issues once the nicotine is out of the system.

As always, thank you for the education!
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Joined: 19 Dec 2008, 00:02

07 Mar 2003, 22:42 #35

I find that article to be SO interesting (and thanks for the further clarification e-mails, Joel).

This is one of the best threads I have read so far (and believe me, I'm reading and reading and reading). What struck me was this - I found that in my later smoking days - maybe about 6 or so months before my quit, every time something happened that made me happy or excited, I'd REALLY crave that smoke. You always hear how people "need a cigarette" when they are stressed or angry or need to calm down...But one of my biggest needs (besides after eating) was when I was HAPPY.

I wonder if I was trying to more fully experience happiness because the nicotine addiction was minimizing my natural high?

Wow, very interesting. Thanks so much for all of this insight!!

ComicForces - 2 weeks TODAY!!
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Joined: 18 Dec 2008, 23:57

31 Jul 2003, 06:34 #36

I thought the article below would be good to attach here. too. You will see that the science of nicotine manipulation has been around for a long time. The one way for you to stop having to manipulate nicotine forever is to stick to the commitment you made when you joined Freedom to never take another puff!

Joel

Expert: Ammonia added to cigarettes Testimony continues in Minnesota's lawsuit against tobaccoFebruary 4, 1998
Web posted at: 10:24 p.m. EST (0324 GMT)
ST. PAUL, Minnesota (CNN) -- Tobacco companies began adding ammonia compounds to cigarettes in the 1960s to boost the effect of nicotine on smokers, according to an expert witness in Minnesota's lawsuit against the tobacco industry.

Pointing to internal company documents, Channing Robertson, testifying on behalf of the state Wednesday, said that in 1965, scientists at R.J. Reynolds, trying to find out why their Winston brand was losing ground to Philip Morris' Marlboro brand, discovered that Marlboro contained ammonia compounds.

Robertson, a Stanford University professor of chemical engineering, said ammonia increases the nicotine potency of cigarettes by increasing the amount of nicotine contained in the vapor smokers inhale.

In the 1970s, Reynolds started adding ammonia and "slowly but surely, everyone fell in line," he said.

By 1989, documents showed that tobacco companies were using more than 10 million pounds of ammonia compounds each year, Robertson said.

And adding ammonia wasn't the only strategy tobacco companies used, according to Robertson.

Brown & Williamson Tobacco Corp. developed a genetically altered strain of tobacco with twice the nicotine content and used it in cigarettes sold in the United States, Robertson testified.

An undated Brown & Williamson internal document described a "Y-1" tobacco strain with a nicotine content of 6.5 percent by weight.

"Through genetic engineering they were able to develop a tobacco strain with twice as much nicotine as it might otherwise have," Robertson said.

"I am aware that the Y-1 product was contained in cigarettes sold in the United States," Robertson said.

The existence and sale of the high-nicotine Y-1 tobacco has been reported before. A California biotechnology company pleaded guilty in January to conspiring with Brown & Williamson to grow and improve the high-nicotine tobacco abroad from 1983 to 1994, when the export of U.S.-developed seeds without a permit was illegal.

But Robertson's testimony allowed the state to put the information before the jury. Among several allegations, the state accuses tobacco companies of manipulating nicotine levels in cigarettes and conspiring to mislead consumers about the dangers of smoking.

One industry memo showed how tiny ventilation holes were drilled in the sides of filters on low-tar cigarettes. That increased the pH of the tobacco smoke, which also tends to increase the potency of nicotine, Robertson said.

Along the same lines, companies also lowered the sugar levels in tobacco, to increase alkalinity and therefore the amount of nicotine available to smokers in cigarette vapor.

The state of Minnesota and Blue Cross and Blue Shield have sued the tobacco industry to recover the costs of providing health care to smokers.
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Joined: 19 Dec 2008, 01:47

31 Jul 2003, 13:36 #37

I have been going through a rough spot for the past few days and this article helps to shed some light. I am at the point in my quit (23 days) where I am proud of myself (and somewhat incredulous) for getting to this point, but I am still afraid that I'll fail. I am scared to death to fail because I know that if I do fail it will mean my life. I read every day and have learned so much but I know that I still haven't reached the point of acceptance yet. I keep telling myself I have to retrain the brain and I am finding that easier said than done. At this point, I almost feel like I have a split personality - there's the side of me that is thrilled and proud of my quit and that already sees positive results from not smoking, and then there's the side that still misses smoking (I know, I know). If nothing else, it certainly reinforces for me just how addictive nicotine is. I won't smoke today. I'll keep telling myself that everyday until my brain can catch up with my heart. Thanks for being here. Elaine
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Joined: 10 Jan 2009, 00:06

31 Jul 2003, 23:34 #38

This article makes so much sence to me for some reason. Thank-you for sharing. I will have to show it to my 20 year old son who smokes and is thinking about quitting.
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Joined: 18 Dec 2008, 23:57

03 Oct 2003, 05:57 #39

I brought this one up earlier today for one member asking about the pharmacology of nicotine action. The commentary that I wrote the day this article was released talks a little bit more about the psychology of smoking that goes along with the findings of this report. This commentary also addresses another issue which was raised today as to how a person should handle a significant other who smokes.
From: Joel. Sent: 3/14/2002 8:03 AM
I remember in my early days of learning about other drug addictions, it became very obvious to me why crack cocaine was so addictive and why cocaine addicts would go through such great lengths and seemingly sacrifice everything in order to get the drug. It was capable of releasing so much dopamine that it was depleting the body's normal supply. Then when a person would do anything that would normally bring pleasure--with the minimal amount of dopamine left, normal activities that used to bring about pleasure seemed to become empty or meaningless. This is why people using cocaine found themselves losing interest in other things that should have been important--in a real sense--they were losing their ability to get pleasure out of pleasurable things.

It seems that this parallels to a degree what happens to smokers. Not only is nicotine releasing the same neurotransmitter, but it is impairing the mechanism to shut down the action of dopamine. Again, the end result is things that should be pleasurable will become a bit diminished by this chronic action.

The cost of such chronic pleasure is the minimizing of real life. That is what the real toll of smoking is--and the real benefit of quitting. Once again you can feel good from accomplishments. I think that is why people take greater pride in things after they quit.

I always joke with spouses who call me up saying they don't know what they can do to make their husband or wife quit smoking. They often ask me if they should threaten to leave the spouse if he or she doesn't quit. I always warn them to be careful when making such a threat. Giving a smoker a choice between take me or your cigarettes, you'd be surprised at how often "me" is going to be left behind.

Again, here you can see why. The normal pleasures brought about by a relationship are minimized if dopamine is in fact impaired--the smoker is in a sense incapable of feeling as good from a relationship or any other activity.

But the smoker needs to understand that to ever be able to fully appreciate life itself, they need to stop taking drugs that interfere with normal life pleasures. The answer is not to find a drug that works better. As this article so eloquently points out at the end, "It would be hard to design a drug that acts on the reward center that would be more effective than nicotine."I suspect it could be done though--but the end result would just be another drug that is robbing the user of the ability to feel pleasure from pleasurable things. This in itself is robbing the user of the ability of a quality life.

Yes nicotine being delivered in a cigarette form is addictive and deadly. But even without the other chemicals additional health consequences--nicotine itself is robbing the individual of really experiences little life's pleasures--and this is a travesty in itself. Again, the solution is not another drug that is even better--the solution is to let your body get back to normal and never be thrown so off track again by knowing to never take another puff!

Joel

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Joined: 18 Dec 2008, 23:57

16 Feb 2004, 09:09 #40

Nicotine Increases Alcohol Craving
Smoking Tobacco Linked to Alcohol Relapse
[/size]
[/size]People who smoke and try to quit drinking have a more difficult time not relapsing, because new scientific evidence indicates that nicotine may actually cause a craving for alcohol. If you combine this factor with another new study which indicates that nicotine addiction may be as powerful as an addiction to heroin, smokers who want to stop drinking face an extremely difficult battle indeed.

Although many treatment programs and self-help support groups recommend addressing "one addiction at a time," treatment approaches that insist that clients give up all addictive substances simultaneously may be more effective, according to these new studies.

Alcohol-Nicotine RelationshipLed by Toronto's Dr. Dzung Anh Le, a study on rats by Canadian and U.S. scientists has found that nicotine use increases alcohol consumption, and the two addictions may work hand in hand.

The research relevant to humans who drink both excessively and moderately, said Dr. Le. It suggests that to quit drinking, a person might also have to give up smoking as well. "It has a lot of implications for treatment strategy," said Dr. Le, of the Centre for Addiction and Mental Health. "What we knew before is alcohol and tobacco are extensively co-abused. We wanted to find a biological basis for this co-dependency."

Dr. Ted Boadway of the Ontario Medical Association said although treating dual addictions is already a cornerstone of many therapies, anti-smoking strategies do not always emphasize curbing alcohol intake. Guidelines on stop-smoking approaches usually do not consider the effect alcohol may have on smokers. The study appears in the U.S. journal Alcoholism: Clinical and Experimental Research.

The ResearchIt is nicotine, the addictive ingredient in cigarettes, which leads to an increase in alcohol consumption, said Dr. Le and fellow researchers at the Indiana University School of Medicine. "Of the study's five experiments on rats, three confirmed researchers' suspicions that nicotine and alcohol "can act through the same rewarding system in the brain," said Dr. Le.

Both nicotine and alcohol lead to the release of dopamine, the "feel-good brain chemical," although the mechanism by which this occurs is not completely understood, Dr. Le said. "Repeated exposure to nicotine through smoking can enhance the pleasurable effects of alcohol, and there's probably some biological basis for this," although it's not completely understood.

The remaining two experiments in Dr. Le's study examined nicotinic receptor antagonists in the brain, and whether they could be altered to block the effects of nicotine and alcohol.




Highly AddictiveMeanwhile, the Royal College of Physicians in Britain released a report calling nicotine "a powerful addictive substance on a par with heroin and cocaine" which should be controlled like a drug or medicine. The report said cigarettes are nicotine delivery products and said nicotine addiction should be recognized as a major medical and social problem. "It is time for nicotine to become a major health priority," Sir George Alberti, the president of the college, said.

The tobacco industry disputed the report's findings.

These new reports provide scientific evidence that those who try to quit drinking, but continue to smoke, face a more difficult problem than those who do not smoke, or who quit smoking and drinking simultaneously.

Other CravingsAlso this week, National Institute on Drug Abuse researchers released two studies that found that craving for nicotine appears to be linked to increased craving for illicit drugs among drug abusers who also smoke tobacco. The two studies, said NIDA Director Dr. Alan I. Leshner, "add very strong behavioral evidence to other research that suggests common characteristics and interactions between tobacco use and opiate and cocaine use. They also suggest that smoking cessation programs should be offered as part of other drug treatment programs."

In one of the studies, researchers found that the amount of cocaine and heroin use was directly related to the level of tobacco use. "The more cigarettes smoked, the more likely the person was to use illegal drugs," said Dominick Frosch, a doctoral student at San Diego State University.
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Joined: 07 Jan 2009, 19:23

17 Feb 2004, 09:12 #41

I had a couple quits before this one and noticed that i drank less alcohol when I was quit did anyone notice that. I think it had to do with the fact that I felt more depressed when i smoked.
just another benefit of not smoking that i will continue to do as long as I NEVER TAKE ANOTHER PUFF.
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Joined: 18 Dec 2008, 23:57

28 Mar 2004, 06:33 #42

I see we have a few new members who are not only ex-smokers but also in recovery from alcoholism. I thought they would appreciate the information provided in this article.
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Joined: 18 Dec 2008, 23:57

30 Oct 2004, 21:41 #43

The above Canadian government nicotine addiction warning label left many wondering if Canada wasn't overstating the power of this amazing chemical. As shown below the research neurochemical links between nicotine and heroin continue to grow more interesting. Still only one rule ... no nicotine just one day at a time ... NTAP! John (gold x5)
U-M team reports first evidence that smoking
affects brain's natural "feel good" chemical system
October 26, 2004 - University of Michigan Health System
Brain scan study suggests nicotine alters smokers' brain chemistry in ways that could help explain craving and satisfaction



SAN DIEGO - Smokers often say that lighting up a cigarette can calm their nerves, satisfy their craving and help them relax.
A map of the brain showing the concentration of receptors for the brain's own "feel good" chemicals, called endogenous opioids. The red, orange and yellow areas have the highest concentrations of receptors, and therefore the most activity of opioid chemicals. In the U-M study, smoking caused major changes in the activity of the opioid system in several of these areas.
Now, a team of University of Michigan scientists is reporting new evidence of why that might be: Smoking produces major changes in the flow of "feel good" chemicals between brain cells, both temporarily and long-term. And those changes in flow match up with changes in how smokers say they feel before and after smoking.

It's the first time smoking has been shown to affect the human brain's natural system of chemicals called endogenous opioids, which are known to play a role in quelling painful sensations, heightening positive emotions, and creating a sense of reward. It's the same system that is stimulated by heroin and morphine.

The research team, from the U-M Medical School, will present the results Tuesday afternoon in a lecture at the annual meeting of the Society for Neuroscience.

The new results come from a pilot study involving a small group of young male pack-a-day smokers and non-smoking comparison subjects. Despite their study's small size, the researchers say the surprisingly large effect on opioid levels they found suggests a promising road for further discovery. That may lead to better understanding of why smoking affects people the way it does - including the mystery of why it's often so hard to quit, despite tobacco's many health dangers.

"It appears that smokers have an altered opioid flow all the time, when compared with non-smokers, and that smoking a cigarette further alters that flow by 20 to 30 percent in regions of the brain important to emotions and craving," says David J. Scott, a graduate student in the U-M Neuroscience Program who will present the results. "This change in flow as seen on a brain scan correlated with changes in how the smokers themselves reported feeling before and after smoking."
The smokers in the study first smoked two special cigarettes that had almost no nicotine, then two regular cigarettes. All the while, they had their brains scanned and were asked to rate how they felt using a rating called the VAS scale. This graph shows that as the smokers switched to regular cigarettes, they felt less alert, anxious and craving, and more relaxed. This matched the changes in their brain chemistry.
Scott and his colleagues made the findings using a type of brain scanning called positron emission tomography, or PET, imaging. This allowed them to literally see activity in the endogenous opioid system when the study participants first smoked a special cigarette with almost no nicotine, and then smoked a regular cigarette. Before, during and after the scans, the participants rated how relaxed, alert, sick and nervous they felt, and how much they were craving tobacco.

The new findings confirm previous animal studies, and add to scientists' previous understanding of how smoking affects the flow of another "feel good" chemical in the brain, called dopamine. Now, the team is studying the interaction of dopamine and opioids in the brains of smokers and non-smokers.

They also hope to look at underlying genetic differences that might explain variations between people in response to nicotine - and perhaps differences in how easily people become addicted to cigarettes or quit smoking.

"The interaction of tobacco, and especially nicotine, with brain chemistry is a fascinating area that we're just beginning to understand, especially when it comes to correlating neurochemistry with behavior," says study leader Jon-Kar Zubieta, M.D., Ph.D., a U-M psychiatrist and neuroscientist. "Just as with the 'hard' drugs of abuse, such as heroin and cocaine, the phenomena of pleasure, addiction, increased tolerance and craving from tobacco are firmly rooted in neurochemistry."

Adds veteran tobacco researcher and U-M emeritus pharmacology professor Ed Domino, Ph.D., "Nicotine addiction is one of the most destructive forces in human health, and we must increase our comprehension of it in order to defeat it. This study represents a key step toward that goal."

Zubieta's team has spent several years developing and testing a way of using PET imaging to study the endogenous opioid system, and specifically the chemicals called endorphins and enkephalins.

Those are the same chemicals involved in the "runner's high", a pleasurable sensation brought on by strenuous exercise. But they're also important to blocking the flow of painful signals in the brain, and the U-M team has used the PET method to study how opioid levels change in response to pain, and how that response is affected by variations in hormone levels and genetic makeup.

The U-M team's PET scan method doesn't show the flow of opioids directly, but rather the status of tiny receptors on the surface of brain cells. These receptors, called mu-opioid receptors, act like locks that can only be opened when opioid molecules - either made by the brain or introduced from outside - bind to them. Morphine, heroin and some anesthetics produce their respective effects by binding to these receptors, and the drug-overdose treatment called Narcan blocks them.

The lower the level of natural opioids around, the more receptors there are available to other opioids - such as a special molecule developed by the U-M team. It's made of a short-lived radioactive carbon atom attached to a molecule of carfentanil, a morphine-like drug known to bind only to mu-opioid receptors. Using the PET scanner, the team can detect how much carfentanil is binding, and by extension how much natural opioid is flowing in that area.

In order to study the effect of nicotine on the opioid system, the team had to find a way to perform their study in the U-M PET scanner despite the strict no-smoking policy of the U-M's Hospitals and Health Centers. They also had to simulate every aspect of smoking except the nicotine, in order to control for all the other chemicals in tobacco smoke and sensory aspects of cigarette smoking.

So, they rigged up a system that allowed a person to smoke a cigarette while lying in the PET scanner having his or her brain scanned, and collected the smoke to vent it to the outdoors. They obtained special cigarettes from the Phillip Morris Research Center in Richmond, VA that had been treated to remove nearly all the nicotine. And they recruited six male smokers in their 20s who reported smoking more than 14 cigarettes each day.

They asked the participants to refrain from smoking for at least 12 hours before coming in for their scans, and tested their breath to make sure they hadn't cheated. The researchers injected the participants with the radioactive tracer form of carfentanil, and started the 90-minute PET scan. Then, they asked participants to rate their feelings on a sliding scale before lighting up a series of two de-nicotinized cigarettes, again between cigarettes, and again after two normal cigarettes.

At baseline, the smokers shower lower receptor levels before smoking. "This may suggest that continued exposure to nicotine had increased the neurotransmitter levels, that are being released under baseline conditions, for example after overnight abstinence from smoking," says Scott. "We are specifically examining this possibility in ongoing studies."

During the smoking of the de-nicotinized cigarettes, the smokers' brains started to show changes in opioid flow. But after they took a 20-minute break from smoking and then smoked regular cigarettes containing nicotine, the opioid levels changed dramatically.
The orange dots on these brain scans show the areas where the biggest changes in opioid activity took place after smokers began smoking a regular cigarette. On the left is the cingulate, where activity increased 20 percent. On the right is the amygdala, where activity decreased by more than 20 percent.
In the area of the brain called the anterior cingulate, which is involved in emotion and emotion-memory integration, the activity of the opioid system increased by about 20 percent. This meant that far more endorphins and enkephalins were being released during smoking.

But the reverse was true in other key parts of the brain involved in memory, emotion and pleasure: the amygdala, the thalamus and the nucleus accumbens. In all three areas, the opioid system was 20 to 30 percent less active after the nicotine from the cigarettes was introduced.

This sharp drop in activity, most significantly in the amygdala and the thalamus, correlated with simultaneous reports from the smokers about how they were feeling after they smoked the normal cigarettes. As the opioid activity in their amygdala and thalamus decreased, they reported feeling more relaxed, less alert and nervous, and less craving than before.

Since smoking stimulates the release of dopamine in some of the same areas of the brain, Zubieta and his colleagues speculate that the connection between the opioid system and the dopamine system may be an important one to study.

As the research goes forward, the team will be analyzing brain scans, self-reported ratings and genetic samples from more smokers and non-smokers, to give them a better picture of the interaction between nicotine, the opioid system, behavior and inherited traits.

But for the moment, simply having shown that nicotine has an impact on the crucial "feel good" system is reward enough.

The research was funded by the National Institute on Drug Abuse, part of the National Institutes of Health. In addition to Scott, Zubieta and Domino, the research team included Lisong Ni, Ph.D., a research associate in Pharmacology, and Mary Heitzeg, Ph.D., a research fellow in the Department of Psychiatry and U-M Addiction Research Center. Zubieta is a member of the U-M Mental Health Research Institute, and a director of the U-M Depression Center.


U-M reseachers have also studied how the brain's opioid system responds to pain, and how differences in hormone levels and genes may help explain why some people can tolerate more pain than others. For more on this research, see press release Can't stand the pain? Your genes may be to blame or Pain and the brain.

For more information on how the U-M team developed and first tested their approach for making brain scan images that reveal the activity of the opioid system, click here.


Contact: Kara Gavin
(c) copyright 2004 Regents of the University of Michigan

Story Source:
Special Thanks to Sten for bringing this story to our attention!
Last edited by John (Gold) on 10 Jul 2009, 16:54, edited 1 time in total.
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Joined: 18 Dec 2008, 23:57

12 Nov 2004, 01:59 #44

A new member just put up the following article. Being that we have the article discussed in this thread I am combining the two pieces. Although we caution all of our members to clear any articles with management before posting at the board.

Nicotine extends duration of pleasant effects of dopamine
By John Easton
Medical Center Public Affiars[/size]
Brief exposure to low levels of nicotine not only boosts the brain's 'reward' system but also blocks a rival system that limits the duration of such rewards, report University researchers in the March 14 issue of the journal Neuron. The finding helps scientists understand why nicotine addiction takes root so quickly and lasts so long.

In 2000, a team from the same laboratory demonstrated how the first exposure to nicotine can create an enduring 'memory trace,' which instills the desire to repeat the experience and amplifies the pleasing effects of subsequent nicotine exposure. The current paper reveals how nicotine prolongs the reward period by disabling the system that counterbalances the drug's pleasant effects.

The reinforcing effect of nicotine is the primary reason people cannot quit smoking, despite widespread awareness that smoking causes cancer, heart disease, stroke, emphysema, bronchitis, vascular disease, cataracts and impotence. The World Health Organization attributes four million deaths each year to tobacco use.

"It would be difficult to design a better drug to promote addiction to this horrible habit," said neurobiologist Daniel McGehee, Assistant Professor in Anesthesia & Critical Care and director of the study. "It takes only a few exposures to create a lasting memory of the rewards of smoking, which are reinforced by each cigarette smoked. Now we find that nicotine also suppresses the brain's efforts to limit that pleasure."

The brain reward areas serve to acknowledge and reinforce beneficial behaviors, for example, eating when hungry. Specialized nerve cells encourage the body to repeat pleasing behaviors by releasing dopamine, the neurotransmitter associated with pleasant feelings, into these reward areas. "That was good," is the basic message of increased dopamine levels. "Do it again."

Unfortunately, drugs of abuse such as nicotine can usurp those pathways, providing the same sort of encouragement for harmful actions such as smoking.

McGehee and his colleagues, postdoctoral researchers Huibert Mansvelder and Russel Keith, working with brain tissue from rats, demonstrated how nicotine extends the duration of these rewards.

In previous work, McGehee's team showed that nicotine produces pleasure by attaching to the nicotinic acetylcholine receptor found on certain nerve cells. In response to nicotine, these nerve cells release a chemical signal called glutamate, which tells connected neurons to release dopamine. The more these nerve cells are excited, the more dopamine is released and the more pleasant the feeling.

In this paper, the researchers looked at the effects of nicotine on nerve cells that use a different chemical, called GABA, which inhibits dopamine release. These nerve cells have a slightly different version of the nicotinic acetylcholine receptor. Although they respond to the initial nicotine exposure, these receptors quickly become overwhelmed and lose their power to generate repeated releases of GABA. This renders them unable to reign in the excitation caused by nicotine. They remain disabled for up to an hour.

"As a result," said McGehee, "the reward system is turned on right away and it keeps sending reward signals for 60 minutes even though nicotine levels drop off 15 minutes after smoking. We suspect that this ability to extend the reward only enhances the drug's ability to reinforce smoking."

It may also provide a new target for drugs designed to help people stop smoking by interfering with nicotine's effects.


Original publication at http://chronicle.uchicago.edu/020328/nicotine.shtml
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Joined: 19 Dec 2008, 00:01

02 May 2005, 21:17 #45

I just counted and this post has been up 13 times since I quit but I'm only now getting around to really reading it . It's a great eyeopener and a great companion piece to John's Nicotine Addiction 101 . I highly recommend all us addicts to read it and all the responses as well. Steve, striving towards a nicotine free normal for 11 plus months now.
Last edited by ZZRSteve GOLD on 10 Jul 2009, 16:57, edited 1 time in total.
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