Abstract
Two primary systems are particularly involved in setting on the physiological stress response, HPA and sympathetic-adrenomedullary (SAM) system. The present study compared the responses of both the HPA and SAM activities to the acute psychological stress between high and low anxious subjects groups. Healthy subjects at the upper (score: >55) and lower (score: <45) limits of the normal range of a trait anxiety scale in the Spielberger’s Trait Anxiety Inventory. The video of corneal surgery was served as the stressor for 15 min. Unstimulated whole saliva was collected every 3 min throughout the session. Salivary cortisol and amylase were assayed as indexes of the HPA and SAM activities, respectively. Salivary β-endorphin was also assayed as a possible index of HPA activity. There were no differences of all the resting salivary parameters levels between high and low anxious groups. As expected, during the stressful video viewing, all the salivary parameters were significantly increased in both the groups. The high anxious group exhibited lower levels of salivary amylase than low anxious group. However, there were no differences of cortisol and β-endorphin levels between the groups. Thus, high anxious subjects exhibited lower HPA hormone release during stressful video viewing than low anxious subjects. Our findings suggest that high trait anxiety may be associated with an inability to respond with sufficient activation of HPA to acute psychological stress. [Jpn J Physiol 55 Suppl:S207 (2005)]
