Department of Psychiatry, University of Naples SUN, Italy.
Psychol Med. 2011 Sep;41(9):1963-9. doi: 10.1017/S0033291711000092. Epub 2011 Feb 2.
The stress response involves the activation of the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS). As a role for stress in determining of the onset and the natural course of eating disorders (EDs) has been proposed, the study of the psychobiology of the stress response in patients with anorexia nervosa (AN) and bulimia nervosa (BN) should be helpful in understanding the pathophysiology of these disorders. The two neurobiological components of the stress response can be easily explored in humans by the measurement of salivary cortisol and α-amylase response to a stressor. Therefore, we assessed salivary cortisol and α-amylase responses to the Trier Social Stress Test (TSST) in symptomatic patients with AN and BN compared to healthy controls.
Seven AN women, eight BN women and eight age-matched healthy females underwent the TSST between 1530 and 1700 h. Salivary cortisol and α-amylase levels were measured by an enzyme-linked immunosorbent assay (ELISA).
Compared to healthy women, AN patients showed a normal cortisol response to the TSST, although this occurred at significantly increased hormone levels, and an almost complete absence of response of α-amylase. BN women, however, exhibited enhanced pre-stress levels of salivary α-amylase but a normal response of the enzyme and cortisol to the TSST.
These findings demonstrate, for the first time, the occurrence of an asymmetry between the HPA axis and SNS components of the stress response in the acute phase of AN but not in BN. The pathophysiological significance of this asymmetry remains to be determined.
应激反应涉及下丘脑-垂体-肾上腺（HPA）轴和交感神经系统（SNS）的激活。由于应激在确定进食障碍（ED）的发病和自然病程中的作用已被提出，因此研究神经性厌食症（AN）和神经性贪食症（BN）患者的应激反应的心理生物学应该有助于理解这些疾病的病理生理学。应激反应的两个神经生物学成分可以通过测量唾液皮质醇和α-淀粉酶对应激源的反应在人类中轻松地进行探索。因此，我们评估了有症状的 AN 和 BN 患者与健康对照组相比，对特里尔社会应激测试（TSST）的唾液皮质醇和α-淀粉酶反应。
七名 AN 女性、八名 BN 女性和八名年龄匹配的健康女性在 1530 至 1700 小时之间接受了 TSST。通过酶联免疫吸附测定（ELISA）测量唾液皮质醇和α-淀粉酶水平。
与健康女性相比，AN 患者对 TSST 的皮质醇反应正常，尽管这种反应发生在激素水平明显升高的情况下，而α-淀粉酶的反应几乎完全缺失。然而，BN 女性表现出唾液α-淀粉酶的应激前水平增强，但对 TSST 的酶和皮质醇反应正常。
这些发现首次表明，在 AN 的急性阶段，HPA 轴和 SNS 应激反应成分之间存在不对称性，但在 BN 中不存在。这种不对称性的病理生理学意义仍有待确定。
