Chronic cannabis use alters dACC-striatal glutamatergic balance.
Chun S Zuo, Scott E Lukas
Pharmacology, biochemistry, and behavior April 2023 DOI: 10.1016/j.pbb.2023.173544 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational case-control study Peer reviewed |
|---|---|
| Sample size | 30 |
| Population | Chronic cannabis users (n=20) and age- and sex-matched non-using controls (n=10) |
| Duration | Baseline and abstinent days 7 and 21 |
| Measures | Proton MRS (glutamate, GABA), Barratt Impulsiveness Scale-11 (BIS) |
| Topics | Cannabis |
| Keywords | Glutamatergic imbalance Dacc-striatal |
| Key findings | The difference in glutamate concentrations between the dACC and striatum was significantly smaller in cannabis users than controls across baseline and abstinent days 7 and 21, independent of age, sex, or alcohol/cigarette consumption. Among users, this difference correlated with the corresponding GABA difference on day 7 and was negatively associated with monthly cannabis use days on day 21. Users also showed altered self-reported impulsiveness. The authors propose these data provide preliminary evidence that chronic cannabis use may lead to a dACC-striatal glutamate imbalance with poor impulse control. |
Abstract
Prefrontal and striatal glutamate plays an important role in modulating striatal dopamine levels and an imbalance in regional glutamate has been identified in several psychiatric conditions. We hypothesized that this imbalance also exists in cannabis use disorder (CUD). We recently quantified the difference in glutamate of dorsal anterior cingulate (dACC) and striatum regions in the frontostriatal pathway using proton MRS at baseline and on verified abstinent days 7 and 21 in chronic users of cannabis (n = 20) in comparison with age- and sex- matched non-using controls (n = 10). In addition, the Barratt Impulsiveness Scale-11 (BIS) was collected as a measure of inhibitory impulse control of the participants. We found that the difference in glutamate concentrations between the dACC and striatum (ΔdACC-strGlu) of the controls was significantly higher than that of cannabis users across the study timeline (F(1,28) = 18.32, p < 0.0005). The group difference was not affected by age, sex, or alcohol/cigarette consumption. On abstinent day 7, ΔdACC-strGlu was significantly correlated with the corresponding ΔdACC-strGABA among the users (r = 0.837, p < 0.00001). On day 21, ΔdACC-strGlu was negatively associated with monthly cannabis use days (Spearman's rho = -0.444, p = 0.05). Self-reported BIS and its subscales were significantly altered among the users compared to the controls across the study timeline (total F(1,28) = 7.0, p = 0.013; non-planning F(1,28) = 16.1, p < 0.0005; motor F(1,28) = 5.9, p = 0.022; cognitive F(1,28) = 6.1, p = 0.019). These data provide preliminary evidence that chronic cannabis use may lead to a dACC-striatal glutamate imbalance in conjunction with poor impulse control.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |