Research reveals why marijuana can cause schizophrenia
A recent study carried out by the CSIC, in Spain, in collaboration with the Cajal Institute, has found evidence about how cannabinoids regulate the activation of certain nerve regions of the brain .
Similarly, the disorganized consumption of cannabis can deactivate a mechanism more intensely than is necessary, causing some mental disorders, such as psychosis or schizophrenia.
Marijuana and schizophrenia: new evidences of their relationship, according to a new study by the CSIC
If certain alterations in the functioning of neurotransmitters (such as dopamine or glutamate) occur in certain brain regions, they give rise to the manifestation of different pathological behaviors such as schizophrenia . There are several genetic factors that increase the vulnerability of some individuals to this pathology. However, environmental factors and pernicious habits such as the use of marijuana or other substances can trigger an acceleration of the symptoms, or increase their intensity.
An investigation on the possible genetic and epigenetic characteristics discovered that the alteration of the nervous system would not be the main risk factor in the appearance of schizophrenia, but that the cause would be in a poor function of the NMDAr receptor , responsible for neuronal plasticity and memory. For this reason, lacking sufficient glutamate to counteract the effects of the drug, dopamine increases its effect, resulting in a greater predisposition to psychosis and schizophrenia.
The role of cannabis in schizophrenia
Primarily, the cannabionoid system proper to our neuronal chemistry is positive, because it regulates the binding of glutamate with its NMDAr receptor and allows certain neurological processes such as learning or memory. The cannabinoids deactivate this receptor, and in this way a physiological stability is maintained throughout the neuronal system.
However, the system is weak and stability is easily compromised. The exogenous cannabinoids , that is, those produced by the use and abuse of marijuana, significantly increases the inhibition of the NMDAr receptor of the neurotransmitter glutamate, allowing a much more effect, exacerbating the effect of dopamine, and being able to cause psychosis.
The brain, in this situation, tries to prevent that effect from occurring, and some NMDAr receptor release mechanisms are enabled , but this reaction can deactivate the neuronal system, causing a vulnerability that could trigger schizophrenia.
The experts speak
Javier Garzón Niño , one of the researchers, explains:
"Abuse in marijuana consumption produces an imbalance between excitation (NMDAr) and inhibition (own or endogenous cannabinoids). This ends up breaking the balance in favor of inhibition, and consequently generates greater activity in systems regulated negatively by NMDAr, such as the dopaminergic system "Several CSIC scientists pointed out that abuse in the inhaled use of marijuana can produce transient psychosis. But in the case that the bad habit was not eliminated, the deterioration of the central nervous system could be permanent . If we add to these bad habits a genetic predisposition, the chances of developing schizophrenia increase.
