Synthetic cannabinoids, substances contained in many dangerous drugs and similar to cannabis, have a harmful effect that causes convulsions, a team at a national research institute has announced.
The team at the National Center of Neurology and Psychiatry (NCNP) has published the discovery in a U.S. science journal. The team says the achievement shows the harmful effects of dangerous drugs that had previously been unknown.
According to the team, convulsions are triggered by abnormality in the hippocampus, a component of the brain that is closely related to memory. If repeated, convulsions could cause memory disorders or adversely affect the brain's ability to learn.
Cannabis is a downer drug that slows people's movements and cognition, but does not usually cause convulsions.
However, as there are people who fall in a state of confusion after using dangerous drugs, the team conducted experiments in which researchers administered synthetic cannabinoids to mice to examine changes in their brain conditions.
The results show that glutamic acid, a neural transmitter substance that causes excitement, began to be excessively released from the hippocampus in mice several minutes after they were administered synthetic cannabinoids. This made it easier for the mice to develop convulsions.
The researchers say this phenomenon can destroy nerve cells in the hippocampus. The excessive release of glutamic acid continues for several to about a dozen minutes and after the release sharply decreases, downer symptoms follow, according to the team.
Differences in symptoms caused by cannabis and synthetic cannabinoids are believed to be due to differences in their toxicity that causes the release of glutamic acid. The higher the density of a drug is, the more frequently convulsions occur in those who use such substances.
Masahiko Funada, a senior researcher at the center, pointed out that "synthetic cannabinoids can be said to be more harmful than cannabis."