目的：基于5-HT/TRPV4/AQP5探讨抑郁相关干眼大鼠泪液分泌减少的机制。

方法：健康雄性SD大鼠用慢性不可预见性温和刺激(CUMS)构造抑郁模型后，筛选出抑郁相关干眼大鼠8只，空白组为空白大鼠8只，ELISA法比较两组大鼠血清和海马组织5-HT，观察泪腺HE切片和AQP5免疫组化，并通过Western blot和RT-PCR检测两组泪腺中5-HT3R、TRPV4和AQP5表达。

结果：抑郁相关干眼组泪液分泌明显减少(P=0.001)，血清和海马5-HT水平明显下降(均P<0.05)，泪腺AQP5抗体免疫组化阳性率明显低于空白组(P<0.001)，同时泪腺中5-HT3R、TRPV4和AQP5蛋白和基因表达明显下降(均P<0.05)，并且泪腺组织切片未见明显炎性细胞。

结论：抑郁相关干眼的发生可能与非炎性的5-HT/TRPV4/AQP5机制有关。

METHODS:Healthy SD male rats were established with chronic unpredictable mild stress(CUMS)method to establish a depression-induced dry eye model(n=8), and the control group was blank rats(n=8). The ELISA method was used to compare the 5-hydroxytryptamine(5-HT)in serum and hippocampal tissue of the two groups, and the HE sections of lacrimal gland and AQP5 immunohistochemistry were observed. Western blot and RT-PCR were used to detect the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland tissue of the two groups of rats.

RESULTS:The tear secretion in the depression-induced group was significantly reduced(P=0.001), the serum and hippocampal 5-HT levels were significantly reduced(all P<0.05), the expression of AQP5 antibody in the lacrimal gland immunohistochemistry was significantly lower than that in the control group(P<0.001), the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland was significantly reduced(all P<0.05), and no obvious inflammatory cells were found in the lacrimal gland tissue sections.

CONCLUSION:Depression-related dry eye may occur through a non-inflammatory 5-HT/TRPV4/AQP5 mechanism.