PPD免疫小鼠胸腺内降钙素基因相关肽能神经纤维的可塑性

Plasticity of calcitonin gene-related peptidergic nerve fibers in the mouse thymus following PPD immunization

目的 观察免疫应答时胸腺内降钙素基因相关肽(CGRP)能神经纤维的可塑性 ,为CGRP在胸腺的调节作用提供线索。方法 用PPD免疫Balb/c小鼠 ,胸腺切片用免疫组织化学法处理 ,光镜下观察。结果 在正常Balb/c小鼠胸腺被囊、小梁内有较丰富的CGRP能神经纤维分布 ,胸腺实质中也有阳性纤维存在。用PPD免疫 2 8d后 ,胸腺被囊、小梁内血管周围的CGRP阳性纤维明显增加 ,这些纤维直径较粗、膨体少 ,多数围绕血管形成网状 ;有的聚集成束直行。胸腺实质内阳性纤维的数量少 ,免疫后较对照组略有增加 ,分布不均。此外 ,胸腺髓质中的一些较大的、三角形或椭圆形的上皮样细胞 ,亦呈CGRP免疫反应阳性。结论 CGRP与胸腺在免疫应答时的结构。

Aim To elucidate the plasticity of calcitonin generelated peptidergic(CGRP) nerve fibers in mouse thymus and to provide clues for the roles of immunomodulation of CGRP.Methods Balb/c mice were immunized peritoneally by purified protein from tuberculinderivatives(PPD). Sections of the thymic tissues were treated immunohistochemically and oberserved microscopically. Results In normal group, there were relatively abundant CGRPlike immunoreactive(LI) fibers in capsule and tubercle. A few positive fibers were seen in parenchyma as well. Twenty eight days after PPD immunization, the perivesicular CGRPLI fibers were significantly increased. These fibers were thick in diameter with few buttons and formed reticular structures surrounding blood vessels or bundles going straightly.The CGRPLI fibers in parenchyma of the thymus were slightly increased in number and distributed unevenly. In addition, a few big triangular or ovoid epitheliallike cells in the medulla of thymus were also CGRPLI. Conclusion The present results indicate that CGRP is related to the changes of structure and function of thymus during immune response.