Salivary chromogranin-A as a marker of psychological stress during a cognitive test battery in humans

Abstract

The purpose of the present study was to evaluate the salivary Chromogranin-A (CgA) response to the psychological stress induced by a cognitive test battery. The subjects were 14 healthy volunteers administered the cognitive test battery CogScreen Aeromedical Edition (CogScreen-AE). CogScreen-AE is a test of reaction time and fundamental cognitive ability in the assessment of aeroplane pilots. The subjects were given five batteries of the test (1st ∼ 5th) on separate days with 2 week intervals. Saliva samples were collected at 20 min before the test (BASE), immediately before the test (PRE), in the middle of the test (MID), and 5 min after the test (POS) for each subject. The concentration of CgA was determined by enzyme-linked immunosorbent assay. ANOVA revealed a significant by time interaction (BASE, PRE, MID and POS) without a significant effect of battery interaction (1st, 2nd, 3rd, 4th and 5th). The CgA concentration increased at PRE (2.46 ± 0.24 pmol·mg protein^{− 1}) from BASE (1.19 ± 0.10 pmol·mg protein^{− 1}). CgA level remained increased in the MID (2.90 ± 0.26 pmol·mg protein^{− 1}) and remained high in the POS samples (2.81 ± 0.23 pmol·mg protein^{− 1}). Salivary CgA remained at basal levels during a control study over the same time course without exposure to CogScreen-AE. The changes in salivary CgA secretion as a result of exposure to a cognitive task may indicate psychological stress in humans.

• Cognitive task
• CogScreen
• Psychological stress
• Sex differences
• Sympatho-medullary activity