Marijuana Protects "Stressed" Rats from Opiate AddictionComments (1)
Rats that grow up in stressful environments get addicted to opiates more easily than rats that grow up under normal conditions. However, if "stressed" rats are given high doses of THC (the active ingredient in marijuana) during adolescence they become far less addicted to opiates given later in life.
Can smoking marijuana as a teen protect a person from opiate addiction as an adult?
French scientist Dr. Valerie Dauge led a research team out of the Laboratory for Physiopathology of Diseases of the Central Nervous System (France) that investigated the influence of THC on morphine dependence.
She and her research team had earlier determined that rats deprived of their mothers for significant periods each day during the first days of life (stressed rats) become more susceptible to morphine addiction later in life. Developmental stress seems to cause lasting changes to the functioning of the enkephalinergic system (the brain's opioid system).
In her latest research work, she led a team that investigated what effect the administration of THC might have on later in life susceptibility to morphine addiction for rats that were stressed early in life - and for rats that grew up under normal conditions.
The research team administered high doses of a synthetic THC during the adolescent period of a rat's lifecycle; between the ages of 35 and 48 days. Two weeks later, rats were given morphine over a period of days and tested for their development of addiction.
The measures used to gauge the degree of addiction in a rat include observing place preference for environments in which morphine is available and testing brain samples for opiate receptor density and other biological markers.
- The researchers found that THC exposure during adolescence offered substantial protection from morphine addiction to the rats that grew up maternally deprived.
- Conversely, THC exposure during adolescence for rats that grew up under normal conditions increased susceptibility to addiction.
THC helped stressed rats avoid addiction, but predisposed the "normal" rats to addiction.
Dr. Dauge writes that this may help to explain why some adolescents use marijuana as self medication, and hopes that the research may lead to novel treatments for opiate dependence and withdrawal.
The full text of the research findings can be read at the online journal, Neuropsychopharmacology.