The sex hormones that bathe a fetus in the womb are some of the earliest and most potent determinates of gender differences in brain structure and social behavior. But other chemicals produced by the human body more subtly tweak the neural pathways underlying these distinctions. Endocannabinoids, natural compounds in the brain that excite the same receptors as marijuana, influence gender-specific behaviors, according to a study published in November in the Proceedings of the National Academy of Sciences USA.
Desiree Krebs-Kraft of the University of Maryland School of Medicine, Baltimore, counted the number of actively dividing glia (nonneuron brain cells) in the medial amygdala (MeA) of four-day-old rats. The MeA controls gender-specific differences in youthful play and regulates mating, parenting, aggression and territoriality in adults.
Krebs-Kraft found that females had more dividing MeA glia than males did. But when the researchers gave newborn rats a drug that mimics the effect of endocannabinoids on brain cells, the rate of cell division in females slowed to the same pace observed in male brains. The drug also changed behavior. Juvenile male rats usually engage in more social play than females, but female rats that received the drug frolicked just as much as the males.
Marijuana affects the mind because substances in the plant called cannabinoids imitate the naturally occurring endocannabinoids found in the brain. “Our results show that endocannabinoids are part of a natural signaling system that underlies the establishment of sex differences in the brain that are an important part of social behavior,” explains Margaret McCarthy, one of the study’s co-authors. “This would suggest that the use of cannabis during pregnancy could alter those systems and have unintended consequences,” she says, though cautioning that much more research is needed to say for sure. Studies have shown that the cannabinoids in marijuana can in fact breach the placenta, so an indulgent mother is smoking for two.
Curiously, the cannabinoid treatment had no effect on cell division or play behavior in males. The researchers found that male rats have inherently higher levels of endocannabinoids in their brains than females, so trying to give the males a little boost did not cause any measurable changes.
This article was originally published with the title Marijuana and Maleness.
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Add CommentI believe it is a matter for the majority of people to see that the whole cannabis prohibition, the whole DEA "dogma" that "marijuana is a dangerous drug without accepted medical use" be exposed in its anti-scientific, deceptive nature. Cannabis is not physically addictive as it lacks the recognizable "physical withdrawal syndrome" (like opiates, or alcohol, for example); the so-called "gateway drug theory" has been proven to be nonsense by a scientific research, and was even declared "half-baked" by a recent study; drug Marinol, much touted by the DEA, is not at all the same as medicinal cannabis which, as opposed to Marinol, has over 70 active compounds interacting in therapeutic ways. Cannabis decriminalization is followed by a decrease (not an increase) in "teenage use", as the example of Portugal clearly shows, and (with another major scare-tactic disintegrating), smoking cannabis does not increase one's risk of lung cancer; combine all this with the violence-suppressing qualities of cannabis use, its propensity to be a "safe alternative" to alcohol/hard drugs, its remarkable medicinal properties, and then see if the DEA "dogmas" have any factual foundation and not just an empty talk that is being enforced by a version of philosophical "radical pragmatism" which basically "allows" its followers to disregard the truth in favor of, let's say, DEA "dogma", with such a dogma being constantly "reinforced" by a consciousness of "guilt" and "fear". "Radical Pragmatism" was at the basis of Illinois patients being denied their medicine, because the DEA intimidated enough "law-makers" with the "non-existing entity" of a "gateway drug theory. The same way, some rogue politicos in Montana are trying to trample the will of Voters of that state by "repealing" the medical marijuana law! So, what we (and I mean, all of us) need to do is spread this scientific knowledge (along with the refutation of "dogma"), so that even for the politicians this becomes a question of either siding with fear and ignorance I doubt that any of these crooked politicos will enjoy a "legacy" of him remaining silent when the modern-day "storm-troopers" dragged a cancer-afflicted granny to jail for using medicinal cannabis. Let's not forget to ask our politicians as well as to why they are "crying broke" and yet, at the same time keep financing the so-called "marijuana enforcement" while most of the country wants this rather harmless natural substance decriminalized altogether, and definitely legalized when it comes to its many remarkable medicinal uses.
Reply | Report Abuse | Link to thisPlease refer to support for the statement, "smoking cannabis does not increase one's risk of lung cancer."
Reply | Report Abuse | Link to thisIt's completely anti-intuitive but apparently true. Type "marijuana does not increase incidence of lung cancer" into google. Here's just one of the many pages that come up:
Reply | Report Abuse | Link to thishttp://www.webmd.com/lung-cancer/news/20060523/pot-smoking-not-linked-to-lung-cancer
Cannabis is not physically addictive as it lacks the recognizable "physical withdrawal syndrome" (like opiates, or alcohol, for example);
Reply | Report Abuse | Link to thisYou have either smoked your common sense away or you have never smoked.
It does have a nasty withdrawal that lasts about a week. I have known people that have had to see a doctor for the depression that followed weeks later.
The rest of your information is false too. Your one of the people who want social welfare (everyone else's tax dollars to pay people like you to stay high.)
It not only causes brain cancer, but other cancers too. Not a good cover for mental illness or deviant behavior. You know the really stupid things people think and do while stoned. Get your facts straight.
"the so-called "gateway drug theory" has been proven to be nonsense by a scientific research, and was even declared "half-baked" by a recent study;"
Reply | Report Abuse | Link to this-- My understanding is that this misconception (or better yet, misinformation) is that when marijuana is illegal, people go buy it from drug dealers who often have other 'real' drugs which some people end up experimenting with for whatever reason. Not that this is a strong scientific argument, but legalizing it cuts down on the black market (obviously) and the opportunities for susceptible people to be exposed to other drugs...The "gateway drug" angle has always been one of the silliest to me. Personally, I've never sat around and smoked a bowl then said "what I could really use right now is some heroin!"
If you want to be a stoner...fine. But addiction should have consequences. Drunks fear the breatholizer. Stoners should have the same consequences for dangerous behavior. More than half the legal medical users in Colorado are between the ages of 18-24. They don't have cancer or AIDS or MS. They are STONERS. Legalize personal growing, create an instant check for intoxication, and stoners are no different than drunks. Duh.
Reply | Report Abuse | Link to this@Notslic
Reply | Report Abuse | Link to thisfair enough, but you are relying on a false premise -- marijuana is no where near as dangerous as other drugs, including alcohol and tobacco, and the downside to being a "stoner" is mostly just that some people will call you names like stoner as if the word itself is it's own premise, conclusion and entire argument, and that you may lack motivation to do things. But saying "stoners are no different than drunks, duh" is flat out wrong. Check out the emergency rooms and see how many people are in there for "marijuana poisoning" or being the victim of a "high driver". Google the "death due to marijuana" statistics. Basically non-existent. How many domestic violence cases involve people that are high? Have you EVER heard of that? One single case?
Alcohol damages, and in some cases, destroys the bodies of 'drunks' and alcohol is responsible for the death of innocents all the time. There is no weed analog to MAAD. That's not an accident. I was a bit rowdier in my younger days, but I've never been in a bar fight w/ someone high on weed. Drunk? It's almost a given. Other than the old school "reefer madness" scare tactics, there is nothing concrete that demonstrates that marijuana is dangerous, and certainly nowhere near as dangerous as cigarettes and alcohol. Smoke or don't smoke, but legalization of pot will not create a generation of zombies, and it has almost nothing to do w/ anyone other than the person smoking. Plus, it would be California's (where I live) biggest cash crop, I've heard $9billion a year. Taxing that would solve alot of problems. It's mostly just the people that want gov't to stay out of their lives, but want to tell people what they can do at the same time that are anti-pot. Pot may make you a stoner, but only the individual is damaged. Alchol and cigarettes kill people and cost this country and tax payers alot of money...money they can use to buy weed!
mbdsta. I can't argue against the upside of smoking weed. I smoked an ounce a week of the GOOD Mexican throughout the 70's and 80's. I had no problem leading a moral life, developing a successful law practice, and putting myself in a position to retire at 45 and enjoy the rest of my life. I even smoked a fatty right before arguing in front of the 9th Circuit Court of Appeals, and was published for creating new law. I was a professional stoner, and it appears that you are also. But let's look at the downside.
Reply | Report Abuse | Link to thisFirst, there is a big difference between a pro and a rookie. I challenge you to not smoke at all for a couple months and then take a couple rippers of that sweet store-bought stuff that is available on every corner in SoCal. Then try to drive. When you smoke all day every day you are just maintaining. When you smoke rarely, you get high as a kite. The reason that there are no statistics regarding driving deaths or injuries due to smoking is that there is not an immediate test available and no statutes specifically aimed at driving while stoned. Cops are only interested in getting you for possession or dealing. Did you ever wonder why all the stoners say "YES" when cops ask to search their car?:) There are also many people who drive while over the alcohol limit who are not a danger. But the law is enforced anyway with dire consequences.
You also write of taxing weed. All the stores pay tax right now on the weed they sell and California still has a $20 billion deficit. I think the taxing to balance the budget thing is a little misleading. Also, there are a lot of pot addicts (and alcohol, and heroin, and crystal, etc.) who spend money that they shouldn't on weed. If you aren't Bill Gates, there is probably something more important that you should spend your money on.
Regarding the health issues, the prohibiltion on research is the reason that there are no statistics in this area also.
Getting to the article...I always had it in the back of my mind that chicks who smoke dope seemed more masculine and less girlie-girl (but definitely horny). Now there is some support. But I will say that smoking never prevented me from getting in a bar fight. Now my smoking is limited to the occasional ski, concert (Red Rocks is the best venue in the world to be stoned at) or fishing day when I don't drive. I make it an event and it is more memorable and potent that way than the everyday thing.
I hope you come back to this post and read my genuine (and without malice) comments. Please reply if you do.
Cheers!! Jeff
The last time I checked, the word combination "you are" when contracted is spelled "you're" not "your". The interesting thing about your rant is the person you are ranting against has superior writing skills and his comment contained no spelling errors.
Reply | Report Abuse | Link to thisAs far as welfare state pot smokers, Bill Gates is a regular smoker, as was Carl Sagan and Richard Feynman. If smoking cannabis is such a stupefying endeavor, then why isn't your name among the scientific elites? Surely you must be more intelligent and productive than Richard Feynman, so I am eager to hear your interpretation on quantum chromodynamics. Also, I am wondering what software company have you founded which is bigger than Microsoft. What is your excuse for not out achieving Gates, Sagan and Feynman?
An honest, scientific and unemotional assessment shows cannabis to be far less dangerous than tobacco or alcohol, and even less dangerous than hydrogenated fats found in food. The question for you is, which is more important, facts and objectivity, or reference group obedience and engaging in histrionic namecalling frenzies? Prove you are more accomplished and more intelligent than Gates, Sagan and Feynman and then I will agree that you may have some validity to your position, however rudely expressed.
@notslic
Reply | Report Abuse | Link to thisGreat post,and taken in the tone in which it was intended ;-)
"I had no problem leading a moral life, developing a successful law practice, and putting myself in a position to retire at 45 and enjoy the rest of my life. I even smoked a fatty right before arguing in front of the 9th Circuit Court of Appeals"
That in particular was very poignant and it appears we have quite a bit in common. I lead a (pretty much) moral life, practice law in the 9th circuit (though I've never argued in front of it) and I plan on enjoying the rest of my life! Good points, well made and well taken. I agree that driving while high is or can be just as dangerous as driving drunk. I've seen plenty of the demonstrations in parking lots w/ cones set up and they show that anyone that is intoxicated by anything is dangerous behind thousands of pounds of metal travling at any speed. They may not be able to test for it yet, but I'm sure (or I should say, I'm assuming) that if I cop pulled someone over that smelled like marijuana, the cop wouldn't send him on his way. I don't do criminal law so in some ways I'm talking out of my nether regions, but I thought that the crime was driving while "intoxicated" not just driving while drunk. In other words, you can also be cited or taken out of your car for driving after taking too much Nyquil, or anything that makes you dangerous. I agree in that sense that driving while high and driving while drunk are probably indistinguishable in any meaningful sense. But in terms of the practical reality, there are very likely far fewer high drivers than drunk drivers. Every restaurant or bar you walk into presents the opportunity to many to become drunk drivers (meaning over .08, not sloshing around necessarily) but not to get high and get behind the wheel. I think my point was coming more from an anecdotal perspective -- people that get high, while they may think they understand string theory all of a sudden (!) don't usually get violent or aggressive, but just the opposite (again, usually). My understanding of alcohol for instance is that it triggers a rise in estrogen for instance, which is why drunk people, including guys, get that teary-eyed "I LOVE YOU MAN!" thing going after too many shots of JD (I've been guilty of that lol) and after too many tequila shots, get into fights. I think operating heavy machinery under ANY influence should be punishable and punished, but as to the point of the danger to the individual and the danger and cost to society, I think legal alcohol and cigs far outstrip "Old Toby"
You can tell I'm a lawyer by the fact that I used up almost all the characters alotted lol. Anyway, re taxing it, I think the point of making it legal is that it would kill the black market, which I'm assuming is still bigger than the legal market by a larger margin (again, I'm assuming this). That would increase the current tax revenue while allowing the gov't to control the potency and quality while decreasing the access to it by kids or people w/ criminal records (incl/ for driving while high for instance). Ironically, I'm watching a show on History channel right now called "Marijuana A chronic History" which reports that there are 192million users worldwide, making it by far the most used drug on the planet. The fact that there are ZERO deaths attributed directly to it (whether due to lack of statistics or other reasons) is very poignant. Plenty of people will die tonight due to alcohol, and emergency rooms will fill up with them for injuries,alcohol poisoning, violence and the like. I saw an article re a study that extrapolates from the effect of THC on rats that a human would have to smoke 30,000 joints to o.d. on weed. While any drug, incl/ weed has a disproportionately deleterious effect on kids, I'd rather have kids w/ weed problems than drinking problems if given the choice. I like your point re "pros" and "rookies" and agree 100%. But it seems to me that the biggest downside of weed is that it makes you lethargic and drains your motivation, but that just keeps people in their houses and on their couches. People that smoke think they're smarter than they really are, but people that are drunk think they're bullet-proof (again, been guilty of that plenty of times lol) and for some reason, makes people more social, which means more drunk driving and more fights etc. But good points definitely, and something to think about. From an enjoyment perspective I've found that hangover effect is also much more pronounced w/ alcohol, and overall, alcohol damages the organs more...If pot was legalized, some huge percentage of the prison population, largely non-violent, would be out of the system, and people that are otherwise good people (or at least law abiding) wouldn't be costing tax payers so much to keep locked up. Finally, I concur re women and weed...I have empirical evidence that backs up your research...in fact, I am going to conduct further studies tonight ! lol Nice conversation here. I wonder if Scientific American expected this...maybe if they've been smoking...
Reply | Report Abuse | Link to thisInterestingly, this article was not about the merits of smoking marijuana, the arguments for legalizing marijuana or the moral capacities of individuals who choose to smoke. It was, in fact, discussing an interesting biological mechanism which may or may not have an impact on the medical advice given to pregnant women.
Reply | Report Abuse | Link to thisWhile I cannot extrapolate to the wider population based upon this anecdotal situation, I do have to wonder whether this might be related to the hypothesis that marijuana affects normal cognitive function. Then again, maybe its just all the lawyers commenting on this column.
I think we would be friends.
Reply | Report Abuse | Link to thisCheers! Jeff
"While I cannot extrapolate to the wider population based upon this anecdotal situation, I do have to wonder whether this might be related to the hypothesis that marijuana affects normal cognitive function. Then again, maybe its just all the lawyers commenting on this column."
Reply | Report Abuse | Link to thisOr maybe you should smoke a joint and relax. It was just good clean fun between people who decided they could think independently enough to talk about whatever they wanted, even if it strayed from the initial topic. For my money, the conversation was quite a bit more interesting than the article...which may be why no one talked about it...
That was good for a laugh :) Sorry, if it was at your expense.
Reply | Report Abuse | Link to thisNo problem at all ;-). Taken as intended I think. Sitting here polishing off 2 fingers of Lagavulin and doing a fantasy baseball mock draft at 12:45 am, so what do I know, lol! I don't think I've ever posted in a Scientific American article comments section, but oddly enough, I keep checking back here...it's almost like having the munchies!
Reply | Report Abuse | Link to thisGoogle cannabinoids and cancer. Cannabis smokers.have a "substantially lower rate" of head and neck cancers by one study. U of Solermo Italy has done several studies proving cannabinoids are pallative and curative on cancers,particularly brain cancers. Though numerous studies have attempted to probe a causal link between smoked cannabis and cancer, they actually showed cannabis smokers have a lower rate of lung cancer than non-smokers.
Reply | Report Abuse | Link to thisis it a female power-
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