In this study, we assessed behavioral responses to social separation at 8 months of age and
cerebrospinal fluid (CSF) concentrations of biogenic amines and metabolites at 8 and 18 months
of age in 12 rhesus monkeys derived from either stressed or undisturbed pregnancies. Compared
to controls from undisturbed pregnancies, prenatal stress-derived monkeys had higher
concentrations of 3-methoxy-4-hydroxyphenylglycol (MHPG), and 3,4-dihydroxyphenylacetic
acid in CSF than controls. Norepinephrine and MHPG response to stress were both correlated
between 8 and 18 months of age. There were few group differences in behavior during social
separation; however, several behavioral differences between groups were found when monkeys
were reunited with cage mates. Prenatally stressed monkeys spent more time clinging to their
surrogates and exploring (including eating and drinking), while controls showed more
locomotion and social play with their cage mates. Collectively, our findings suggest that chronic
unpredictable psychological stress during pregnancy has long-lasting effects on noradrenergic
and dopaminergic activity and behavior in the offspring of gestationally stressed primate
mothers.