Nanbu Patricia Naomi, Hosoe Takahiro, Hamai Yuko, Shigematsu Akiyo
Institute of Whole Body Metabolism, Nauchi, Shiroi-shi and Chiba-ken, Japan.
Eur J Drug Metab Pharmacokinet. 2007 Jul-Sep;32(3):149-62. doi: 10.1007/BF03190477.
A marked difference in the healing process of the inferior vena cava in rats following a stab with a 17-G (1.48 mm phi) ultrahard zirconium ceramic (Zr) needle and with a common stainless steel (St) needle (also 1.48 mm phi was observed. This was investigated in vivo by histological imaging and biochemical micro-autoradiographic imaging using [2-(14)C]-thymidine as a biomarker in vivo. On the first day after the stab with either, the Zr or the St injection needle, the tunica adventitia showed the most pronounced damage, as evidenced by a large puncture wound characterized by blood congestion, but with few inflammatory cells being observed. A marked contraction of the tunica media was observed. The depth of the injury reached the tunica layer, but amounted to less than 1/3 of the needle diameter. Loose fragments of the endothelial lining were detected, together with scattered red corpuscles. The survival rate of the experimental animals amounted to less than 40% on the 3rd day after the stab by either the Zr or St needle, due to the large needle diameter. In addition, histological imaging of the wound area in the endothelial layer and tunica media showed considerable congestion and inflammation, which limited the evaluation of the regeneration status of the inferior vena cava of the surviving animals. Results were obtained from a few animals that displayed satisfactory recovery status. On the 3rd day after the stab by either the Zr or St injection needle, a relatively large proportion of the hemostatic clots became incorporated into the collagenous tissue, i.e. the tunica adventitia. A marked contraction of the tunica media was also observed, similar to that on the 1st day, following the needle injury. In the case of the endothelium (tunica intima), the injury caused by the Zr needle was reinfiltrated by adult stem cells 3 days after the stab, but the tunica media, composed of endothelial cells, still contained relatively contracted collagenous material. In addition, several interesting cell colonies were observed in the medial layer at the short distance from the boundary of the damaged tissue. It was assumed that these colonies produced medial tissue composed of collagenous supporting tissue or smooth muscle cells. In the experiment using the St needle, the incorporation of [2-(14)C]-thymidine into the nucleus of the stem cells was observed in the small capillaries of the tunica media, but not in the support cells of the latter.
用17G（直径1.48毫米）超硬锆陶瓷（Zr）针和普通不锈钢（St）针（直径也为1.48毫米）刺伤大鼠下腔静脉后，其愈合过程存在显著差异。通过组织学成像和生化微放射自显影成像在体内对此进行了研究，使用[2-(14)C]-胸苷作为体内生物标志物。在用Zr针或St针注射刺伤后的第一天，外膜显示出最明显的损伤，表现为以充血为特征的大穿刺伤口，但观察到的炎症细胞很少。观察到中膜明显收缩。损伤深度到达内膜层，但小于针直径的1/3。检测到内皮衬里的松散碎片以及散在的红细胞。由于针直径较大，在被Zr针或St针刺伤后的第3天，实验动物的存活率低于40%。此外，内膜层和中膜伤口区域的组织学成像显示有相当程度的充血和炎症，这限制了对存活动物下腔静脉再生状态的评估。从少数恢复状态良好的动物身上获得了结果。在用Zr针或St针注射刺伤后的第3天，相当大比例的止血凝块融入了胶原组织，即外膜。还观察到中膜明显收缩，与针刺伤后第1天的情况类似。在内皮（内膜）方面，Zr针造成的损伤在刺伤3天后被成体干细胞重新浸润，但由内皮细胞组成的中膜仍含有相对收缩的胶原物质。此外，在距受损组织边界较短距离的中层观察到几个有趣的细胞集落。推测这些集落在产生由胶原支持组织或平滑肌细胞组成的中层组织。在使用St针的实验中，在中膜的小毛细血管中观察到[2-(14)C]-胸苷掺入干细胞的细胞核，但在后者的支持细胞中未观察到。
