Background

Although findings from both animal and clinical research indicate that the blood-brain barrier (BBB) contributes to the pathogenesis of various psychiatric disorders (including depression), the underlying mechanisms are unknown. We investigated the levels of the tight-junction proteins claudin-5 and aquaporin-4 (AQP-4) in astrocytes of learned helplessness (LH) rats (an animal model of depression) and non-LH rats (a model of resilience).

Methods

We administered inescapable mild electric shock to rats and then identified the LH and non-LH rats by a post-shock test. The expressions of claudin-5 and AQP-4 in several brain regions of the LH and non-LH rats were then evaluated by a western blot analysis.

Results

The levels of both claudin-5 and AQP-4 in the CA-1 and CA-3 hippocampal areas of the LH group were significantly lower than those of the control group, whereas those of the non-LH rats were not significantly different from those of the control and LH rats.

Conclusions

These results suggest that LH rats but not non-LH rats experienced down-regulations of claudin-5 and AQP-4 in the CA-1 and CA-3. It is possible that a region-specific modulation of claudin-5 and AQP-4 is involved in the mechanisms of vulnerability but not resilience in depression.

中文翻译：

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抑郁症习得性无助模型大鼠海马 CA-1 和 CA-3 区域中claudin-5和aquaporin-4的减少

背景

尽管动物和临床研究的结果表明血脑屏障（BBB）有助于各种精神疾病（包括抑郁症）的发病机制，但其潜在机制尚不清楚。我们研究了习得性无助(LH) 大鼠（抑郁动物模型）和非 LH 大鼠（恢复力模型）星形胶质细胞中紧密连接蛋白 claudin-5 和水通道蛋白 4 (AQP-4) 的水平。

方法

我们对大鼠进行不可避免的轻度电击，然后通过电击后测试来识别 LH 和非 LH 大鼠。然后通过蛋白质印迹分析评估LH 和非LH 大鼠的几个脑区域中claudin-5 和AQP-4 的表达。

结果

LH组海马CA-1区和CA-3区claudin-5和AQP-4水平均显着低于对照组，而非LH组大鼠与对照组无显着差异。对照组和 LH 大鼠。

结论

这些结果表明，LH 大鼠而非非 LH 大鼠在 CA-1 和 CA-3 中经历了 Claudin-5 和 AQP-4 的下调。Claudin-5 和 AQP-4 的区域特异性调节可能与抑郁症的脆弱性机制有关，但与恢复力无关。