A joint research group consisting of Associate Professor Yujiro Yamanaka of the Graduate School of Education, Hokkaido University, Hidemasa Motoshima, and Kenji Uchida of the Central Research Institute of Yotsuba Dairy Co., Ltd. I found that the reaction was different between morning and night.
Cortisol is a typical hormone controlled by the body clock and shows a clear diurnal rhythm of high in the morning and low in the night.It is also an activity index of the hypothalamus-pituitary-adrenal cortex system (HPA axis system), which is responsible for the stress response of the living body.Previous studies have shown that normal stress responses are seen from morning to daytime with high cortisol levels, but have not been validated at nighttime with low cortisol levels.
Therefore, in this study, we compared the diurnal rhythm of cortisol in saliva in daily life and the magnitude of stress response when a psychological stressor was given in the morning and evening in healthy adult men and women.As a result, it was found that there was no stress response to psychological stressors at night when the cortisol concentration was low.In other words, it was suggested that the defense mechanism of the living body could not adapt well to the stressor from the outside at night.
From this study, it was found that the time difference observed in the stress response of the HPA axis system is related to the rhythm of cortisol concentration controlled by the body clock. It is expected to be applied to the prevention of diseases caused by.
Paper information:[Neuropsychopharmacology Reports] HPA axis differentially responses to morning and evening psychological stress in healthy subjects
