Lovallo William R, Farag Noha H, Vincent Andrea S, Thomas Terrie L, Wilson Michael F
Veterans Affairs Medical Center, Department of Psychiatry and Behavioral Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
Pharmacol Biochem Behav. 2006 Mar;83(3):441-7. doi: 10.1016/j.pbb.2006.03.005. Epub 2006 May 2.
Caffeine elevates cortisol secretion, and caffeine is often consumed in conjunction with exercise or mental stress. The interactions of caffeine and stress on cortisol secretion have not been explored adequately in women. We measured cortisol levels at eight times on days when healthy men and women consumed caffeine (250 mg x 3) and underwent either mental stress or dynamic exercise protocols, followed by a midday meal, in a double blind, placebo-controlled, crossover design. Men and women had similar cortisol levels at the predrug baselines, but they responded differently to mental stress and exercise. The cortisol response to mental stress was smaller in women than in men (p=.003). Caffeine acted in concert with mental stress to further increase cortisol levels (p=.011), the effect was similar in men and women. Exercise alone did not increase cortisol, but caffeine taken before exercise elevated cortisol in both men and women (ps<.05). After a postexercise meal, the women had a larger cortisol response than the men, and this effect was greater after caffeine (p<.01). Cortisol release in response to stress and caffeine therefore appears to be a function of the type of stressor and the sex of the subject. However, repeated caffeine doses increased cortisol levels across the test day without regard to the sex of the subject or type of stressor employed (p<.00001). Caffeine may elevate cortisol by stimulating the central nervous system in men but may interact with peripheral metabolic mechanisms in women.
咖啡因会提高皮质醇分泌，并且咖啡因常与运动或精神压力一同摄入。咖啡因与压力对女性皮质醇分泌的相互作用尚未得到充分研究。我们采用双盲、安慰剂对照、交叉设计，在健康男性和女性摄入咖啡因（250毫克×3次）并接受精神压力或动态运动方案，随后享用午餐的日子里，八次测量他们的皮质醇水平。男性和女性在用药前基线时的皮质醇水平相似，但他们对精神压力和运动的反应不同。女性对精神压力的皮质醇反应比男性小（p = 0.003）。咖啡因与精神压力共同作用进一步提高皮质醇水平（p = 0.011），男性和女性的这种效应相似。单独运动不会增加皮质醇，但运动前摄入咖啡因会使男性和女性的皮质醇升高（p值均小于0.05）。运动后用餐后，女性的皮质醇反应比男性大，且咖啡因摄入后这种效应更明显（p < 0.01）。因此，应激和咖啡因引起的皮质醇释放似乎是应激源类型和受试者性别的函数。然而，在整个测试日，重复摄入咖啡因会提高皮质醇水平，而与受试者性别或所采用的应激源类型无关（p < 0.00001）。咖啡因可能通过刺激男性中枢神经系统提高皮质醇，但可能与女性外周代谢机制相互作用。
