MARIJUANA AND IT'S ADDICTIVE EFFECTS ON THE BODY 


Craig Coker

     The dominant fear about marijuana in the 20th century has
been that its effects were somehow similar to the dangerously addictive 
effects of opiates such as morphine and heroin.  Scientists feared that, 
like opiates, it had an extremely high potential for abuse and addiction.
Despite widespread decriminalization of marijuana in the United States in 
the 1970's, this concern has remained the basis for federal law and 
policies regarding the use and study of marijuana.  But the discovery of 
THC receptor sites in the brain refutes that thinking and may force 
scientists to re-evaluate their positions.

     The next century will veiw the 1988 discovery of the THC receptor 
site in the brain as the pivotal event which led to the legalization of 
marijuana.  The receptor breakthrough occurred in 1988 at the St. Louis 
University Medical School where Allyn Howlett, William Devane, and their 
associates identified and characterized a cannabinoid receptor in a rat 
brain.  Receptors are binding sites for chemicals in the brain, chemicals 
that instruct brain cells to start, stop, or otherwise regulate various
brain and body functions.  Before this discovery, no one knew for sure 
just how the psychoactive chemical in marijuana workes on the brain. 
Throughout the 1970's and 1980's, researchers made tremendous strides in 
understanding how the brain works by using receptor sites as switches 
which respond to various chemicals by regulating brain and body functions.
The chemicals which trigger receptors are known as neurotransmitters.
The brain's neurotransmitters are known as endogenous ligands.  In many 
instances, drugs mimic these natural chemicals working in the brain.
Scientists are just now confirming their determinations as to which 
endogenous ligands work on the cannabinoid receptors.  It is likely that
the neurotransmitter which naturally triggers cannabinoid receptors is 
one known as anandamide.  

     Many important brain functions which affect human behavior involve 
the neurotransmitter dopamine.  Serious drugs of abuse such as heroin and 
cocaine, interfere with the brain's use of dopamine in manners that can 
seriously alter an individual's behavior.  A drug's ability to affect the 
neural systems related to dopamine production has now become the defining
characteristic of drugs with serious abuse potential. 

     The discovery of a previously unknown system of cannabinoid neural
transmitters is profound.  While century-old questions such as why 
marijuana is nontoxic are finally being answered, new fascinating 
questions are emerging.  In the words of Israeli researcher Raphael 
Mechoulam, the man who first isolated the structure of THC, "Why do we 
have cannabinoid receptors?"  Medical research into the health effects of 
cannabis have also matured.  In a comprehensive 1986 article in the 
Pharmacological Review, Leo Hollister of the Stanford University School 
of Medicine concluded that "compared with other licit social drugs, such 
as alcohol, tobacco and caffeine, marijuana does not pose greater risks."  
He also wondered if these currently licit drugs would have seen such 
popular acceptance based on our current knowledge of them.

     The primary question was how do cannabinoids work on the brain?  The 
triennial reports from the National Institute on Drug Abuse summarizing 
research on marijuana had begun to omit references to research on 
marijuana related brain damage and instead focus on brain receptor 
research.  A comprehensive article by Renee Wert and Michael Raoulin was 
published in the International Journal of the Addictions in 1986 detailing 
the flaws in all previous studies that claimed to show brain damage 
resulting from marijuana use.  As Hollister independently concluded, 
"Brain damage has not been proved."  The reason, obviously, is that the 
brain was prepared in some respects to process THC.

     Dopamine is a neurotransmitter which is associated with extremely 
pleasurable sensations so that the neural systems which trigger dopamine 
release are known as the "brain reward system."  The rewarding properties 
of dopamine are what accounts for animal studies in which animals will 
forgo food and drink or willingly experience electric shocks in order to 
stimulate the brain reward system.  It is now widely held that the drugs 
of abuse directly or indirectly affect the brain reward system.  The key 
clinical test of whether a substance is a drug of abuse potential or not 
is whether administration of the drug reduces the amount of electrical 
stimulation needed to produce self-stimulation response or dopamine 
production.  This is an indication that a drug has reinforcing properties 
and that an individual's use of the drug can lead to addictive and other 
harmful behavior.  To be precise, according to the Office of Technological 
Assessment (OTA):  "The capacity to produce reinforcing effects is 
essential to any drug with significant abuse potential."

     Marijuana should no longer be considered a serious drug abuse 
because, as summarized by the OTA:  "Animals will not self-administer THC 
in controlled studies...Cannabinoids generally do not lower the threshold 
needed to get animals to self-stimulate the brain reward system, as do 
other drugs of abuse." 



Marijuana does not produce reinforcing effects.


     Advances in neurobiology are redefining the scientific basis for 
addiction. These advances have important ramifications for addiction 
treatment, and for the treatment of numerous organic diseases and 
conditions.  More importantly for marijuana users, these advances in 
neurobiology will ultimately force changes in the law.  

     However, the abuse question is the pre-eminent issue in attempts to 
reform marijuana laws, and it is the weak link upon which the entirety 
of marijuana prohibition rests.  The most recent research indicates that 
marijuana does not have a high potential for abuse, especially relative 
to other drugs such as heroin, cocaine, sedatives and amphetamines.

     In conclusion, with the discovery of cannabinoid receptor sites, and 
their relevance to the understanding of THC in the brain, provides the 
basis for a new challenge to the legitimacy of marijuana's illegal status.
There have been many profound breakthroughs that I have shown that prove 
that marijuana is not addictive and the brain even has special receptors 
specifically for processing marijuana.  I hope that this report has been 
informative and been able to give you some insight into the addictive 
properties (or rather, the lack) of marijuana.








                               WORKS CITED

1.  "Interview with Prof. Raphael Mechoulam, Codiscoverer of THC"
       	International Journal of the Addictions, 21(4-5), 579-587, 1986

2.  Hollister, L.E., "Health Aspects of Cannabis", Pharmacological 
	Reviews, 38:1 (1986), 1-20

3.  "Marijuana and Its Effects". Washington, D.C. December 1991. pg 3

4.  M.E. Martin, B., "Neurobiology of Marijuana Abuse"  201-206, 1992

5.  Mechoulam, R. Cannabinoids as Therapeutic Agents, Boca Raton: CRC
 	Press.  1986

6.  Herkenham, M., "Cannabinoid Receptor Localization in Brain:
 	Relationship to Motor and Reward Addiction"  19-32, 1992


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