Abstract # 129:

Scheduled for Saturday, August 26, 2017 04:30 PM-04:45 PM: (Grand Ballroom) Oral Presentation


A VALIDATION STUDY OF HAIR CORTISOL IN RHESUS MONKEYS

A. Kapoor and T. E. Ziegler
University of Wisconsin-Madison, Wisconsin National Primate Research Center, 1223 Capitol Court, Madison, Wisconsin 53715, USA
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     Analysis of cortisol in hair has become a widespread tool for assessment of hypothalamic-pituitary-adrenal (HPA) axis activity because of its ease of collection and its ability to provide longitudinal data. In order to meaningfully interpret hair cortisol a radio-metabolism study is required to understand hormone incorporation into hair. Tritiated (3H)-cortisol was administered to 4 adult rhesus monkeys (Macaca mulatta) to determine quantity and form of cortisol in hair. Samples of hair were collected from new and previously shaved patches at 2-weeks and 4-weeks. Hair was processed by external wash, grinding, and hormonal extractions. Samples were separated by high-performance liquid chromatography (HPLC) and fractions were collected and radioactivity assessed. Only 1-4 % of the total radioactivity was incorporated into the hair and this was found by the 2-week hair collection. No further radioactivity was found by the 4-week collection. The quantity of hair collected at the 2 and 4-week collections was highly variable between monkeys, indicating that the between-subject hair growth patterns were not consistent. Importantly, for the first time, we showed that centrally administered 3H-cortisol was found in the hair as 3H-cortisol and 3H-cortisone, as well as other glucocorticoid metabolites, which demonstrated that measurement of hair cortisol is representative of circulating cortisol, but may not be the only important measure. Funding sources: NIH P51OD011106, WNPRC Pilot Funding.