Enhancing Brain Pregnenolone May Protect Cannabis Intoxication but Should Not Be Considered as an Anti-addiction Therapeutic: Hypothesizing Dopaminergic Blockade and Promoting Anti-Reward

Many US states now embrace the medical and recreational use of Cannabis. Changes in the laws have heightened interest and encouraged research into both cannabinoid products and the potential harms of Cannabis use, addiction, and intoxication. Some research into those harms will be reviewed here and misgivings about the use of Pregnenolone, to treat cannabis addiction and intoxication explained. Pregnenolone considered the inactive precursor of all steroid hormones, has recently been shown to protect the brain from Cannabis intoxication. The major active ingredient of Cannabis sativa (marijuana), Δ(9)-tetrahydrocannabinol (THC) enhances Pregnenolone synthesis in the brain via stimulation of the type-1 cannabinoid (CB(1)) receptor. This steroid has been shown to inhibit the activity of the CB(1) receptor thereby reducing many of the effects of THC. While this mechanism seems correct, in our opinion, Vallee et al., incorrectly suggest that blocking CB(1) receptors could open unforeseen approaches to the treatment of cannabis intoxication and addiction. In this hypothesis, we caution the scientific community that, other CB(1) receptor blockers, such as, Rimonabant (SR141718) have been pulled off the market in Europe. In addition, CB(1) receptor blockers were rejected by the FDA due to mood changes including suicide ideation. Blocking CB(1) receptors would result in reduced neuronal release of Dopamine by disinhibition of GABA signaling. Long-term blockade of cannabinoid receptors could occur with raising Pregnenolone brain levels, may induce a hypodopaminergic state, and lead to aberrant substance and non-substance (behavioral) addictions.