Stress-induced salivary cortisol secretion during hypobaric hypoxia challenge andin vivourinary thromboxane production in healthy male subjects

Abstract

Few studies have assessed the effects of stress on in vivo platelet activation. In the present study, hypobaric hypoxia induced by rapid decompression during high-altitude simulated flight in a hypobaric chamber was used to evaluate the effects of environmental stress on salivary cortisol and urinary thromboxane metabolite (TXM) excretion, a noninvasive marker of in vivo platelet function. Twenty-one male aviators (mean ± SD age = 36 ± 7 years) experiencing hypoxia by removing their oxygen mask for 4-5 min during a simulated flight to 25,000 ft (7,620 m; pO(2) = 59.17 mmHg) and a matched control group of thirteen flying instructors wearing oxygen masks during the challenge, were studied. Hypobaric hypoxia induced a transient significant increase (P < 0.001) in the aviators' salivary cortisol concentration; the overall pattern of diurnal cortisol fluctuation was maintained in both groups. Urinary TXM showed a significant ∼30% reduction (P < 0.01) after the chamber session in aviators exposed to hypobaric hypoxia, but not in controls. A significant inverse correlation was found between salivary cortisol and urinary TXM in aviators (r = - 0.64, P = 0.0015). Salivary cortisol was a significant predictor (P < 0.001) for urinary TXM concentrations in aviators. In conclusion, here we observed that an acute stress-induced salivary cortisol increase was associated with reduced urinary thromboxane biosynthesis, providing the first indirect evidence for an inhibitory effect of acute stress on in vivo platelet function.

Salivary cortisol and α-amylase: subclinical indicators of stress as cardiometabolic risk

“…Researchers studied salivary cortisol (11,28,30–34,37 –40 ,42 –47,49–54,56–68,70,71) and/or salivary α-amylase response to stress (11,29,32,33,35,36,40–42 ,44 ,48,49,52,53,55,59 ,61,63,66,69–72) for their association with CV/CM items. A substantial number of these studies showed significant correlations between salivary cortisol and/or salivary α-amylase and clinical/subclinical CV/CMR indicators (28,29,31,32,36,37,44,50,55).…”

“…A substantial number of these studies showed significant correlations between salivary cortisol and/or salivary α-amylase and clinical/subclinical CV/CMR indicators (28,29,31,32,36,37,44,50,55). Several studies have demonstrated the association between stress-induced salivary cortisol and/or salivary α-amylase modifications and CV/CMR clinical/subclinical indicators (11,35,47,70,71).…”

Diurnal patterns and associations among salivary cortisol, DHEA and alpha-amylase in older adults

“…The measurement of salivary cortisol, sAA and DHEA is becoming more widely accepted for monitoring changes in HPA and SAM activity under stress-related conditions [35,36,48,49,57]. Changes in salivary cortisol, sAA and DHEA levels, as well as their diurnal fluctuations, are thought to have implications for health [1,70,8].…”

Acute Hypobaric-Hypoxia Challenge and Salivary Cortisol and DHEA-S in Healthy Male Subjects

“…The ratio between the two steroids ( Fig. 2 , right) was quantifi ed, and no statistically signifi cant differences were observed between the cortisol-to-DHEA-S ratios measured on the day of the hypobaric chamber experience and those measured in the no-stress condition (F (2,22) 5 0.251; P 5 0.780).…”

“…Coste et al ( 2 ) suggested that prolonged mild hypoxia altered the expression of the cortisol circadian rhythm. More recently, we were able to show that hypobaric hypoxia induced a large reversible increase in salivary cortisol, with no alteration of the physiological diurnal fl uctuation ( 22 ). These discrepancies prompted us to evaluate in depth the effect of barometric pressure decrease on HPA activity.…”