毛髪コルチゾールの抽出手法の検討─粉砕を必要としない方法について─

抄録

Cortisol that is released into the blood stream in response to psychological stress and accumulates in human hair during its growth. Thus, human hair cortisol (HHC) can be considered a retrospective and long-term index of stress. However, the protocol for HHC determination has technical issues that have to be resolved. One of the issues is that excessive pulverization of hair samples during HHC extraction can reduce extraction efficiency. In the present study, we investigated the effects of hair pulverization and extraction time on HHC extraction. From 20 young participants, HHC was extracted using various protocols for mechanical sample decomposition (powdered using a pulverizer, fragmented using scissors, and untreated 1-cm hair segment) and extraction times (1, 6, 24, 48, and 72 h). We showed that increasing the extraction time increased the amount of HHC extracted. Notably, after 48 h, the amount of HHC extracted peaked regardless of the type of pulverization. Moreover, high correlation of the extracted HHC amount was observed for protocols involving different decomposition procedures when the extraction time was 48 h or longer. Thus, our results indicate that HHC can be purified reproducibly following a protocol without pulverization when the extraction period is over 48 h.