Posted by Zo on March 26, 2002, at 17:49:01
Brain Receptor Tied to Teen Suicide Risk
By Amy Norton
NEW YORK (Reuters Health) - High levels of a particular chemical receptor in the brain may be related to the risk of teenage suicide, findings from a small study suggest.
Although the relationship remains unclear, researchers speculate that this brain characteristic may signal a genetic vulnerability to suicide.
Studying autopsied brain tissue from 30 teenagers who died of suicide or other causes, Dr. Ghanshyam N. Pandey and colleagues found that suicide victims showed higher levels of a particular receptor for the chemical serotonin, which helps relay messages between brain cells.
Serotonin is known to affect mood, and dysfunction in the serotonin system has been implicated in psychological disorders such as depression and anxiety. The receptors Pandey's team studied, known as serotonin 2A receptors, have been found to exist in higher-than-normal levels in the brains of adult suicide victims.
In the current study, the brains of teen suicide victims showed heightened levels of serotonin 2A receptors and greater activity in the genetic machinery churning out the receptor. In addition, this difference was limited to two regions of the brain--the prefrontal cortex and the hippocampus--that are involved in emotion, stress and mental processes such as perception and reasoning.
If this brain-receptor characteristic is indeed genetic, it may indicate an inborn susceptibility to suicide, according to Pandey, a researcher at the University of Illinois at Chicago.
On the other hand, he told Reuters Health, the abnormality may be secondary to changes in other body systems.
But it is at least "quite likely" that teen suicide is related to dysfunction in the serotonin system, since these suicides are frequently driven by impulsive or aggressive behavior, stress or anxiety, Pandey and his colleagues report in the March issue of the American Journal of Psychiatry.
Pandey said these findings suggest it could become possible to spot suicidal individuals based on their serotonin 2A levels. Serotonin also exists in the blood, and in earlier work, his team found that suicidal patients with various mental disorders had higher levels of these receptors in blood cells called platelets.
More broadly, Pandey noted, the identification of the specific biological abnormalities related to suicide could lead to the development of more targeted drugs for suicidal patients.
SOURCE: American Journal of Psychiatry 2002;159:419-429.
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