大鼠喉同种异体移植术后组织学观察

为探讨大鼠同种异体喉移植免疫排斥反应发生的时间和发展过程，共实施大鼠喉移植术３１只。其中对照组（ｎ＝１３）：供、受体均为封闭群ＳＤ大鼠，属同系喉移植术。实验组（ｎ＝１８）：供体为封闭群ＳＤ大鼠，受体为Ｗｉｓｔａｒ大鼠，属同种异体移植术。免疫排斥反应开始于术后第３天，表现为受体颈部皮肤肿胀，淋巴结肿大，７天后颈部皮肤硬肿显著，移植物组织水肿，逐渐被纤维结缔组织包裹。相应的组织学变化特点是：术后第３天变化与对照组基本相同，５天后实验组粘膜上皮逐渐出现鳞状上皮化生，固有层和粘膜下层腺体发生萎缩并消失，横纹肌变性坏死，上述各层组织出现进行性淋巴细胞、单核细胞和多形核白细胞浸润，血管纤维素样变性，管壁增厚，管内血栓形成，１４天后喉移植物的正常组织结构被纤维结缔组织和肉芽组织取代，最终出现完全性变性坏死。由此判断了同种异体喉移植免疫排斥反应发生的时间、顺序和程度，为免疫抑制剂的应用及功效评价提供了客观依据。

Histopathological studies of laryngeal allotransplantation in rats

The establishment of an animal model for laryngeal allotransplantation in rat has enabled us to correlate clinical impressions of laryngeal allograft rejection with histologic data. In this study we used both clinical and histopathologic criteria to define the sequence and time parameters of rejection in histoincompatible vascularized rat laryngeal allografts. Of the 31 rats receiving vascularized laryngeal allografts, 18 served as experimental group, in which allogeneic transplantations were performed from inbred SD to outbred Wistar rats, 13 rats used as controls receiving laryngeal histocompatible transplants. The clinical phenomena of rejection aas started at 3 days post operation, characterized by noticeable dermal swelling and lymphadenectasis of the recipient's neck. At this time, the graft appeared slightly edematous. These changes progressed and were more pronounced by 1 week. Two weeks after operation, the recipients exhibited an inflammatory scar tissue encasing the graft, the normal laryngeal architecture of grafts was invisible. Gross clinical evidence of rejection was well correlated with pathologic findings. Three days following transplantation, there was a slight histologic difference between the experimental group and the control group. Five days later, the surface respiratory epithelium exhibited progressive squamoi metaplasia, and minor salivary glands were mostly atrophic, afterwards extensive loss of acini emerged, with predominant lymphocyte and polymorphonuclear leukocyte infiltration throughout the lamina propria, sub mucosa and the laryngeal adventitia. The arteriolar walls showed fibrinoid changes, with reactive intimal proliferation,and thickening of vessel wall. Focal thrombosis were frequently found. By 2 weeks, the normal architecture of the laryngeal allografts had nearly completely been replaced by fibrovascular connective and granulation tissues. Definition of the time sequence and histopathology of rejection will allow future determination of the efficacy of various immunosupressive agents.