Sood Ankit, Chaudhari Karina, Vaidya Vidita A
a Department of Biological Sciences , Tata Institute of Fundamental Research , Mumbai , Maharashtra , India.
Stress. 2018 Mar;21(2):136-150. doi: 10.1080/10253890.2017.1422488. Epub 2018 Jan 10.
Stress enhances the risk for psychiatric disorders such as anxiety and depression. Stress responses vary across sex and may underlie the heightened vulnerability to psychopathology in females. Here, we examined the influence of acute immobilization stress (AIS) and a two-day short-term forced swim stress (FS) on neural activation in multiple cortical and subcortical brain regions, implicated as targets of stress and in the regulation of neuroendocrine stress responses, in male and female rats using Fos as a neural activity marker. AIS evoked a sex-dependent pattern of neural activation within the cingulate and infralimbic subdivisions of the medial prefrontal cortex (mPFC), lateral septum (LS), habenula, and hippocampal subfields. The degree of neural activation in the mPFC, LS, and habenula was higher in males. Female rats exhibited reduced Fos positive cell numbers in the dentate gyrus hippocampal subfield, an effect not observed in males. We addressed whether the sexually dimorphic neural activation pattern noted following AIS was also observed with the short-term stress of FS. In the paraventricular nucleus of the hypothalamus and the amygdala, FS similar to AIS resulted in robust increases in neural activation in both sexes. The pattern of neural activation evoked by FS was distinct across sexes, with a heightened neural activation noted in the prelimbic mPFC subdivision and hippocampal subfields in females and differed from the pattern noted with AIS. This indicates that the sex differences in neural activation patterns observed within stress-responsive brain regions are dependent on the nature of stressor experience.
应激会增加患焦虑和抑郁等精神疾病的风险。应激反应存在性别差异，这可能是女性更容易患精神疾病的原因。在这里，我们以Fos作为神经活动标记物，研究了急性固定应激（AIS）和为期两天的短期强迫游泳应激（FS）对雄性和雌性大鼠多个皮质和皮质下脑区神经激活的影响，这些脑区被认为是应激的靶点，并参与神经内分泌应激反应的调节。AIS在内侧前额叶皮质（mPFC）的扣带回和下缘亚区、外侧隔区（LS）、缰核和海马亚区诱发了一种性别依赖性的神经激活模式。mPFC、LS和缰核中的神经激活程度在雄性中更高。雌性大鼠齿状回海马亚区的Fos阳性细胞数量减少，而雄性中未观察到这种效应。我们探讨了在FS的短期应激下是否也能观察到AIS后出现的性别差异神经激活模式。在下丘脑室旁核和杏仁核中，与AIS类似，FS导致两性的神经激活都显著增加。FS诱发的神经激活模式在性别上是不同的，雌性的前边缘mPFC亚区和海马亚区的神经激活增强，这与AIS时观察到的模式不同。这表明在应激反应性脑区内观察到的神经激活模式的性别差异取决于应激源经历的性质。
