None of Four Commercially Available Assays Detects Prolactin in Human Saliva (Technical Briefs‪)‬

In psychobiological and psychopathological studies, biological markers are used as indicators for changes in neurotransmitters in the central nervous system. The concentration and/or turnover of serotonin, dopamine, glutamine, and other neurotransmitters can partly be deduced from information obtained on the concentrations of hormones in blood after specific stimulation. This "endocrine window" is of major importance for studies in the field of biological psychiatry. More recently, it has been discovered that the measurement of certain hormones in saliva can be used as a good reflection of the plasma or serum concentrations of these hormones, which certainly seems to be true for steroid hormones such as cortisol, androstenedione, 17-hydroxyprogesterone, and testosterone. Saliva can be collected more easily and more frequently than blood, and its collection causes much less stress. Cortisol measurements in saliva in particular have received much attention.