Past Issues

Neurobiological Aspect of Sex Difference in Stress-related Mental Disorders

Tzung-Lieh Yeh, M.D.1,2 I-Hui Lee, M.D.1,2 Yen-Kuang Yang, M.D.1,2,3 

Background:The sex differences in mental disorders have attracted the attention of researchers. Although the exact sex ratio female to male of prevalence in major depressive disorder varies slightly from culture to culture, most nations have reported a sex ratio close to 2:1. A reverse correlation has been found between the severity of life events and stability of mental disorders. Method:We did the literature review for English papers. This review included four major biological perspectives: (A) the hypothalamic-pituitary-adrenal (HPA) axis, (B) the monoamines in the CNS, (C) the sex hormones and (D) the cerebral regions. Results:The review showed (A) The HPA axis is known to be sensitive to mental illness. But, the HPA axis function, as indicated by plasma cortisol levels, varies in patients with post-traumatic stress disorders (PTSD). Only the PTSD female patients have been found to have low cortisol levels. In addition, the healthy females have higher cortical levels in response to daily stress. (B) Noradrenalin (epinephrine) plays a role in memory consolidation in coping with stress, particularly in females. Higher serotonin transporter availability in response to daily stress is also observed in females. In contrast, males’ dopamine transporter availability is more vulnerable to daily life stress. (C) Estrogen can protect animals and human from stress. (D) Prominent anatomical differences exist in the amygdala and corpus callosum between the two sexes when under stress. Conclusion:Currently, the research of sex differences in stress coping is inadequate. We suggest that the integrating biologic and psychosocial vulnerabilities is an exciting topic for future research, and that a conceptual framework or testable hypothesis to embrace all pathogenesis for the sex differences in stress-coping is needed.
Key Word sex differences, stress coping, mental disorder
Editorial Committe, Taiwanese Journal of Psychiatry
9F-3, 22, Song-Jiang Rd., Taipei 104, Taiwan
Email/ │ TEL/886-2-2567-8295 │ FAX/886-2-2567-8218