Injections of THC, the active principle of cannabis, eliminate dependence on opiates (morphine, heroin) in rats deprived of their mothers at birth. This has been shown by a study carried out by Valérie Daugé and her team at the Laboratory for Physiopathology of Diseases of the Central Nervous System (UPMC / CNRS / INSERM) in the journal Neuropsychopharmacology. The findings could lead to therapeutic alternatives to existing substitution treatments.
In order to study psychiatric disorders, neurobiologists use animal models, especially maternal deprivation models. Depriving rats of their mothers for several hours a day after their birth leads to a lack of care and to early stress. The lack of care, which takes place during a period of intense neuronal development, is liable to cause lasting brain dysfunction. Valérie Daugé's team at the Laboratory for Physiopathology of Diseases of the Central Nervous System (UPMC / CNRS / Inserm) analyzed the effects of maternal deprivation combined with injections of tetrahydrocannabinol, or THC, the main active principle in cannabis, on behavior with regard to opiates.
Previously, Daugé and her colleagues had shown that rats deprived of their mothers at birth become hypersensitive to the rewarding effect of morphine and heroin (substances belonging to the opiate family), and rapidly become dependent. In addition, there is a correlation between such behavioral disturbances linked to dependence, and hypoactivity of the enkephalinergic system, the endogenous opioid system.