A. Heinz et al., IN-VIVO ASSOCIATION BETWEEN ALCOHOL-INTOXICATION, AGGRESSION, AND SEROTONIN TRANSPORTER AVAILABILITY IN NONHUMAN-PRIMATES, The American journal of psychiatry, 155(8), 1998, pp. 1023-1028
Studies on brain serotonin metabolism in human and nonhuman primates h
ave indicated that dysfunction of serotonin transmission may play a ro
le in the biological vulnerability to dependence on alcohol. Among you
ng men, low sensitivity to alcohol intoxication predicts subsequent al
cohol abuse and dependence. Method: The authors used single photon emi
ssion computed tomography and the radioligand [(I)123] beta-CIT ([(I)1
23]methyI 3 beta-(4-iodophenyl) tropane-2-carboxylate) to measure the
availability of serotonin transporters in 11 male rhesus monkeys, and
the monkeys were genotyped for a functional polymorphism of the seroto
nin transporter gene. The 11 monkeys had experienced parental separati
on after birth; their behavior and 5-hydroxyindoleacetic acid (5-HIAA)
concentrations in CSF had been assessed regularly. Results: In the 5-
year-old monkeys, there was a significant negative correlation between
beta-GIT binding to serotonin transporters in the brainstem and 5-HIA
A concentrations in CSF. Animals with greater beta-CIT binding and low
CSF 5-HIAA concentrations displayed greater aggressiveness and were l
ess sensitive to alcohol-induced intoxication. The genetic constitutio
n of the serotonin transporter promoter gene did not significantly con
tribute to the availability of brainstem serotonin transporters as mea
sured by beta-CIT binding. Conclusions: In adult nonhuman primates who
underwent early developmental stress, variables indicating a low sero
tonin turnover rate were associated with behavior patterns similar to
those predisposing to early-onset alcoholism among humans.