1. Association of cannabis with glutamatergic levels in patients with early psychosis: Evidence for altered volume striatal glutamate relationships in patients with a history of cannabis use in early psychosis
- Author
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Sami, M., Worker, A., Colizzi, M., Annibale, L., Das, D., Kelbrick, M., Eranti, S., Collier, T., Onyejiaka, C., O'Neill, A., Lythgoe, D., Mcguire, P., Williams, S. C. R., Kempton, M. J., Bhattacharyya, S., Macherla, P., Prountzos, A., Kitts, R., Vasicuro, L., Taousi, Z., and Tekfi, F.
- Subjects
Psychosis ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Glutamic Acid ,Humans ,Magnetic Resonance Imaging ,Cannabis ,Liver Neoplasms ,Psychotic Disorders ,Hippocampus ,Striatum ,Grey matter ,Molecular neuroscience ,Article ,lcsh:RC321-571 ,White matter ,Cellular and Molecular Neuroscience ,Glutamatergic ,Internal medicine ,medicine ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Biological Psychiatry ,biology ,business.industry ,Carcinoma ,Hepatocellular ,medicine.disease ,biology.organism_classification ,cannabis use ,Psychiatry and Mental health ,Endocrinology ,medicine.anatomical_structure ,Schizophrenia ,striatal glutamatergic levels ,business - Abstract
The associative striatum, an established substrate in psychosis, receives widespread glutamatergic projections. We sought to see if glutamatergic indices are altered between early psychosis patients with and without a history of cannabis use and characterise the relationship to grey matter. 92 participants were scanned: Early Psychosis with a history of cannabis use (EPC = 29); Early Psychosis with minimal cannabis use (EPMC = 25); Controls with a history of cannabis use (HCC = 16) and Controls with minimal use (HCMC = 22). Whole brain T1 weighted MR images and localised proton MR spectra were acquired from head of caudate, anterior cingulate and hippocampus. We examined relationships in regions with known high cannabinoid 1 receptor (CB1R) expression (grey matter, cortex, hippocampus, amygdala) and low expression (white matter, ventricles, brainstem) to caudate Glutamine+Glutamate (Glx). Patients were well matched in symptoms, function and medication. There was no significant group difference in Glx in any region. In EPC grey matter volume explained 31.9% of the variance of caudate Glx (p = 0.003) and amygdala volume explained 36.9% (p = 0.001) of caudate Glx. There was no significant relationship in EPMC. The EPC vs EPMC interaction was significant (p = 0.042). There was no such relationship in control regions. These results are the first to demonstrate association of grey matter volume and striatal glutamate in the EPC group. This may suggest a history of cannabis use leads to a conformational change in distal CB1 rich grey matter regions to influence striatal glutamatergic levels or that such connectivity predisposes to heavy cannabis use.
- Published
- 2020