Background: In vivo studies find altered serotonin function associated with aggressive and suicidal behaviors. Postmortem studies also reveal serotonergic alterations in suicide subjects but have not reported on the relationship between aggression and the serotonin system. We measured 5-hydroxytryptamine 2A (5-HT(2A)) receptor binding in prefrontal cortex of suicide and nonsuicide subjects and explored the relationship between 5-HT(2A) receptor binding, lifetime aggression, and suicide.
Methods: The 5-HT(2A) receptor binding in coronal sections of prefrontal cortex was quantified by autoradiography with [(3)H] ketanserin in 37 suicide subjects and 73 nonsuicide subjects. The relationship between [(3)H] ketanserin binding and lifetime aggression, rated on the Brown-Goodwin Aggression History Scale, was assessed controlling for age and sex.
Results: In suicide subjects, lifetime aggression scores correlated positively with [(3)H] ketanserin binding in all prefrontal Brodmann areas examined, after adjusting for age and sex. This was not the case in nonsuicide subjects. We found no significant differences in aggression scores or [(3)H] ketanserin binding between the suicide subjects and nonsuicide subjects.
Conclusions: The relationship between aggression and 5-HT(2A) receptor binding in suicide subjects, but not in nonsuicide subjects, may reflect differences in the regulation of the 5-HT(2A) receptor related to suicidal behavior and perhaps other proaggressive changes in brains of suicide subjects.