老龄大鼠慢性脑灌注不足脑内白细胞和T细胞的入侵

The activation of T-cells and leukocytes on brain after chronic cerebral hypoperfusion in aged rats

目的 探讨白细胞和 T细胞在慢性脑灌注不足脑损害中的活动。方法 70只老龄 Wistar大鼠持久性双侧颈总动脉结扎 (2 VO) ,其中 12只接受环孢霉素 A(Cs A )治疗。免疫组化法检测白细胞和 T细胞。实验研究为持久性 2 VO 1～ 4月。结果 大鼠慢性脑灌注不足造成了明显的脑损害与白细胞和 T细胞的入侵。1～ 4月 ,白细胞在皮层、白质和海马的活动均减少 ,而 T细胞的活动在皮层下白质增多 ,在皮层和海马减少。同时脑损害加重。Cs A治疗后白细胞和 T细胞的活动明显减弱 ,脑损害减轻。结论 慢性脑灌注不足的病理损害 ,尤其白质损害中 ,T细胞伴有重要作用 ,白细胞仅起次要作用。 Cs A能抑制白细胞和 T细胞的活动 ,从而防治了脑损害。

Objective To investigate the effects of the activation of T cells and leukocytes on the brain damages after chronic cerebral hypoperfusion. Methods Both common carotid arteries were ligated bilaterally in 50 Wistar rats. Twelve of them were filled with cyclosporin A. T cells and leukocytes were observed with immunohistochemistry for CD 4,CD 8 antigens and leukocytes common antigens, respectively. The activation of T cells and leukocytes were then studied from 1 to 4 months after the ligation. Results There were obviously brain damages and the activtion of T cells and leukocytes in cortex, hippocampus and white matter. but the activation of leukocytes was reduced in cortex, hippocampus and white matter. Meanwhile, brain damages becameheavier. In cyclosproin A treated rats, the activation of T cells and leukocytes was significantly reduced, brain damages were much less intense also. Conclusion The activation of T cells may play an important role in the pathogenesis of brain damages, especially in white matter, but the activation of leukocytes may play a little role in the pathogenesis of brain after chronic cerebral hypoperfusion. Cyclosporin A can suppress the activation of T cells and leukocytes, and reduces brain damages after chronic cerebral hypoperfusion.