Enhanced Expression Of Toll-Like Receptor 3 In The Brain Of Subarachnoid Hemorrhage Rats

Objective:To observe the dynamic expression and significance of Toll-like receptor 3 (TLR3) in subarachnoid hemorrhage model (subarachnoid hemorrhage, SAH).Methods:SAH model was established using blood injection into the cisterna magna. Sixty SD rats were randomly divided into sham group and SAH groups (including SAH 1-3-7-days groups).each with 15 rats. The operation steps were the same in groups except the sham group that was injected with saline instead. At different time points after modeling. The mRNA and protein expression of TLR3 was detected using RT-PCR. Western blotting and immunohistochemistry, respectively, Meanwhile, the distribution of TLR3 was analyzed using the immunofluorescence double labeling technique. Results:The mRNA and protein expression of TLR3 was weak in sham group and highly expressed in SAH groups, and the highest expression were found in SAH3-day group. Immunohistochemistry showed that TLR3 was highly expressed in vascular endothelial and hippocampal neurons. The sham group showed a weak TLR3 expression in the cytoplasm, while the SHA group showed the strongly expressed TLR3 mainly in the nucleus and cytoplasm. The result of immunofluorescence also suggested TLR3 was co-expressed in the endothelial cells.Conclusion:The TLR3 expression was enhanced when the rats suffered from SAH, which suggested TLR3 signal factor might play a certain role in the pathogenesis of SAH.