-Saliva is the first body fluid to encounter exogenous materials or gases such as cigarette smoke (CS). The aim of this study was to examine whether smoking affects oral peroxidase (OPO) reactivity to mental stress. The subjects were 39 non-smokers and 10 smokers. In the experiment, the Kraepelin psychodiagnostic test as a psychological stressor and saliva was sampled 30 min before, just before, immediately after, and 30 min after the beginning of the test. OPO reactivity to the test between smokers and non-smokers was measured in addition to uric acid concentration, flow rate, IgA, thiocyanate (SCN − ) concentration, amylase activity as a salivary stress marker, and ultra-weak chemiluminescence (UCL) level, which is indicative of salivary antioxidative and antibacterial abilities. Moreover, we studied the effect of smoking on the response of salivary peroxidase (SPO) and myeloperoxidase (MPO) activity to mental stress, respectively. The results showed that the IgA concentration, amylase activity, SCN − concentration, and UCL level are higher in the non-smoking group than smoking group and the IgA concentration and UCL level increased in the non-smokers significantly just after the Kraepelin test. The levels of SCN − were higher in smokers than in non-smokers and OPO activity was greater in the non-smoking group in all sessions. Furthermore, only the non-smokers had significantly increased MPO activity just after the test. MPO may play a crucial role in the response to acute psychological stress besides inflammation, and CS suppresses this response significantly.

Saliva sampling has the advantage of being noninvasive and stress free. Based on a recent study, salivary ultraweak chemiluminescence (UCL) is a new biomarker of psychologic stress. However, it is not clear what causes changes in the UCL level and whether the change is biologically significant. We investigated the candidates for salivary UCL induced by psychological stressors and discuss the physiologic function of these candidates. Volunteers completed a questionnaire and then performed the Kraepelin test. Saliva was sampled just before, immediately after, and 30 min after the stress exposure. The UCL of saliva significantly increased just after stress exposure (1.56-fold) and returned to prestress levels after 30 min. The concentration of secretory immunoglobulin A also increased significantly and the change in both biomarkers was rapid. Similar significant changes were observed in salivary peroxidase activity and the concentration of thiocyanate (SCN − ). On the other hand, the levels of amylase activity did not significantly increase and the concentration of cortisol increased slowly. Moreover, in the reconstitution experiment, UCL was generated at the same level by a mixture of peroxidase and SCN − at physiologic concentrations. In conclusion, we determined that the Kraepelin test as a mental arithmetic task elicited a significant response in the body and this response can be calculated using salivary UCL. Furthermore, SCN − and peroxidase in the saliva play a key role in salivary UCL.

Response of ultra‐weak chemiluminescence (UCL) in saliva before and after an experimental examination was explored in 10 healthy undergraduate students. Participants were asked to perform a task under supervision that consisted of a serial aseptic manipulation for cell culture. Saliva was collected 30 min before, immediately after, 30 min after and 60 min after the stress exposure. One‐way repeated measures ANOVA for UCL revealed a significant difference across the four measurement occasions (F = 4.45, p < 0.05). Post hoc Dunnett's test clarified that UCL levels right after the stress exposure was significantly greater than that 30 min before the exposure (p < 0.05). The concentrations of secretory immunoglobulin A (sIgA) and cortisol in saliva were also measured. Two‐way ANOVA with repeated measures indicated that UCL and sIgA exhibited the same change pattern in the four occasions (F = 0.28, p = 0.84), whereas UCL changed differently from cortisol (F = 5.82, p < 0.005). It was suggested that salivary UCL may be a sensitive biomarker for acute psychological changes. Copyright © 2005 John Wiley & Sons, Ltd.

The present data suggest that our technique involving lateral slicing of skin tissues and measurement of drug concentrations allows visual understanding of drug dispositions in the skin layers and makes it possible to evaluate the drug levels in the target area of the skin tissue.

No abstract