The 24-hour pattern of prolactin secretion in depressed and normal adolescents

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 interactions were found. With the possible exception of psychosis, dividing the MDD sample based on clinical characteristics failed to reveal differences. These findings are discussed in the context of changes in prolactin in childhood depression using a serotonergic challenge study, as well as in relation to baseline prolactin studies in adult depression.