Mechanisms of gender bias in the response to stress

Depression and anxiety disorders are related to exposure to stress and have been shown to occur twice as often in women as in men. Moreover, women are more prone to develop major depression than men. Numerous epidemiological studies have been done on the subject, as well as several behavioral experiments and histological analyses on rodents, in order to understand the causes and locations of this sexual dimorphism. Despite this, the mechanisms that lead to this greater female vulnerability are still mostly undiscovered. It is known that there are types of stress to which females and males react differently, and several areas are known to be involved in stress management and stress-related disorders. These include the medial prefrontal cortex, the amygdala, the nucleus reuniens and the lateral habenula. In this thesis, three experiments on mice are analyzed that show different reactions of males and females to different kinds of stress, both acute and chronic. In addition, sexual differences emerge in the involvement of various brain areas following stress.