Stress hormone stability: processing of blood samples collected during parabolic flight. A pre-flight comparison of different protocols.

OBJECTIVES: Compare different protocols for blood processing to be used during parabolic flights. DESIGN AND METHODS: Measurement of cortisol (COR), prolactin (PRL), adrenocorticotropic hormone (ACTH), epinephrine (EP) and norepinephrine (NOR) concentrations stored at different temperatures and intervals before analysis.
RESULTS: COR, PRL and NOR showed no changes in concentration between analysis protocols. ACTH dropped by 60% when not analysed within 24 h.
CONCLUSION: A standardised processing protocol that includes a 4-h delay following blood collection is suitable for the assessment of serum stress hormone concentrations.