MOTOR LATERALIZATION, BEHAVIORAL DESPAIR AND DOPAMINERGIC BRAIN ASYMMETRY AFTER PRENATAL STRESS

This paper presents data suggesting a relationship between rat behavio ral despair in the Porsolt test and motor lateralization in the T-maze test. In addition, experimental evidence suggests a functional coupli ng among dopaminergic systems, behavioral despair and motor lateraliza tion. In the first experiment, female, not male. rats with a high leve l of behavioral despair showed a low level of behavioral lateralizatio n. The inverse relationship was found in female offspring of mothers s tressed during gestation. In comparison with unstressed-mother rats, t he female offspring of stressed mothers showed an increase of dopamine (DA) and a decrease of dihydroxyphenylacetic acid (DOPAC) and Homovan illic (HVA) levels and of DOPAC:DA and HVA:DA indexes in the n. accumb ens of the right side of the brain. No significant differences were fo und in the n. accumbens of the left brain. Taken together, the present data provide evidence of a relation between behavioral despair and mo tor lateralization, suggesting that the biological dopaminergic inerva tion of n. accumbens could be the basis for this functional coupling. Because the stress of gestant mothers modified these biochemical and b ehavioral variables, the present study also suggests that lateralizati on of behavior and emotion during adulthood can be modified by prenata l variables. (C) 1997 Elsevier Science Inc.