Plasma prolactin concentrations were measured at 20-min intervals over
a 24-hr period in 49 adolescents with major depressive disorder (MDD)
and 39 normal control adolescents. Neither the pattern nor the amount
of prolactin secretion was significantly different between these two
groups. There were significant gender differences with girls secreting
more prolactin than boys, but no significant gender-by-diagnosis inte
ractions were found. With the possible exception of psychosis, dividin
g the MDD sample based on clinical characteristics failed to reveal di
fferences. These findings are discussed in the context of changes in p
rolactin in childhood depression using a serotonergic challenge study,
as well as in relation to baseline prolactin studies in adult depress
ion.