PMID- 10080858 OWN - NLM STAT- MEDLINE DCOM- 19990507 LR - 20151119 IS - 0889-1591 (Print) IS - 0889-1591 (Linking) VI - 12 IP - 4 DP - 1998 Dec TI - Effect of endogenous cortisol levels on natural killer cell activity in healthy humans. PG - 285-96 AB - The aim of this study was to examine the effects of increasing and decreasing endogenous cortisol levels on natural killer (NK) cell activity in vivo. Normal healthy volunteers participated in the following studies: baseline (n = 27), metyrapone challenge test (n = 10), dexamethasone suppression test (n = 10), and adrenocorticotropic hormone (ACTH) stimulation test (n = 8). Each subject served as his own control for each study. Each subject was tested for NK activity and plasma cortisol levels at 9 a.m., just before the challenge drug administration, and at 10 a.m., except for the dexamethasone study, in which only the 9 a.m. blood was drawn, 10 h after the dexamethasone administration. On the baseline study day, a significant decrease in plasma cortisol levels was found from 9 to 10 a.m. (p <.02) along with a significant increase in NK activity (p <.001). On the metyrapone test day, plasma cortisol levels at 10 a.m. were significantly reduced (p <.005) as expected, while NK activity at the same time point was not affected and was increased to an extent equivalent to the baseline study day. On the dexamethasone test day, plasma cortisol concentrations were significantly decreased (p <.0001) as compared to the same time point on the baseline day, without any significant change in the NK activity. On the ACTH test day, plasma cortisol rose significantly at 10 a.m. (p <.02), with no change in NK activity. We conclude that plasma cortisol alone has no significant effect on NK activity in vivo. CI - Copyright 1998 Academic Press. FAU - Bodner, G AU - Bodner G AD - The Laboratory of the Biology of Addictive Diseases, The Rockefeller University, New York, New York, 10021-6399, USA. FAU - Ho, A AU - Ho A FAU - Kreek, M J AU - Kreek MJ LA - eng GR - DA00049/DA/NIDA NIH HHS/United States GR - DRR00102/RR/NCRR NIH HHS/United States GR - P50-DA05130/DA/NIDA NIH HHS/United States PT - Clinical Trial PT - Journal Article PT - Research Support, Non-U.S. Gov't PT - Research Support, U.S. Gov't, P.H.S. PL - Netherlands TA - Brain Behav Immun JT - Brain, behavior, and immunity JID - 8800478 RN - 0 (Glucocorticoids) RN - 60617-12-1 (beta-Endorphin) RN - 7S5I7G3JQL (Dexamethasone) RN - 9002-60-2 (Adrenocorticotropic Hormone) RN - WI4X0X7BPJ (Hydrocortisone) RN - ZS9KD92H6V (Metyrapone) SB - IM MH - Adrenocorticotropic Hormone/pharmacology MH - Adult MH - Cytotoxicity Tests, Immunologic MH - Dexamethasone MH - Female MH - Glucocorticoids MH - Humans MH - Hydrocortisone/*blood MH - Killer Cells, Natural/*physiology MH - Male MH - Metyrapone/pharmacology MH - Stimulation, Chemical MH - beta-Endorphin/blood EDAT- 1999/03/19 00:00 MHDA- 1999/03/19 00:01 CRDT- 1999/03/19 00:00 PHST- 1999/03/19 00:00 [pubmed] PHST- 1999/03/19 00:01 [medline] PHST- 1999/03/19 00:00 [entrez] AID - S0889-1591(98)90533-5 [pii] AID - 10.1006/brbi.1998.0533 [doi] PST - ppublish SO - Brain Behav Immun. 1998 Dec;12(4):285-96. doi: 10.1006/brbi.1998.0533.