Central serotonergic function in parasuicide.
1. Central 5-HT is thought to be involved in neuronal inhibition and as such as a modulating influence in restraining the organism from responding to (e.g., especially adverse) stimuli. 2. Evidence for a role of central 5-HT in suicide arises from reduced concentrations of brain 5-HT or 5-HIAA in brain stem, reduced binding of [3-H]-IMI in brain tissue of frontal cortex/hypothalamus, and increased binding of radioligands to 5-HT-2 receptors in the frontal cortex. 3. Evidence for a role of central 5-HT in parasuicide arises from reduced concentrations of lumbar CSF 5-HIAA, reduced PRL responses to d,l-fenfluramine challenge, and increased CORT responses to 5-HTP challenge. 4. Since reduced central 5-HT activity appears to be consistently associated with impulsive aggression, it is possible that suicidal and parasuicidal acts in individuals with evidence of reduced central 5-HT activity are a manifestation of reduced impulse control. 5. Agents which enhance central 5-HT function and/or diminish the activity of neuronal systems involved in arousal (e.g. norepinephrine or dopamine) should be efficacious in reducing parasuicidal behavior.