Dolfi A, Lupetti M, Bianchi F, Michelucci S
Department of Histology and General Embryology, University of Pisa, Italy.
J Anat. 1988 Feb;156:17-26.
The aim of the present experiment was to verify whether the origin of the DIA is ectodermal or endodermal. A rabbit serum against the epithelial cells of the final portion of the cloaca was prepared. The indirect immunofluorescence method was applied to strips obtained with a cryostat, carefully cut in such a way as to include a part of the cloaca, the burso-cloacal stalk, the DIA, and the bursal plicae. In this way, it was possible to demonstrate that the epithelium of the cloaca, of the burso-cloacal stalk, and of the DIA exhibited an intense fluorescence that could not be observed at the level of the epithelium of the bursal plicae. These findings would appear to indicate that the DIA, like the cloaca and the burso-cloacal stalk, is ectodermal in origin. Furthermore, histological study revealed that the DIA exhibits close structural analogies with the dorsal wall of the cloaca. In both areas, unorganized lymphoid infiltrations of the tunica propria can be seen, and the epithelium does not show any follicle-associated epithelial cells. The glands often assume the aspect of dilated crypts containing intestinal transit material. The epithelium of these glands reveals lymphoid infiltrations at various points, and it is not uncommon to detect accumulations of cells in their lumina. Several groups of eosinophilic granulocytes can also be observed in the tunica propria of these two areas, with a clear predominance at the level of the DIA. These similarities between the cloaca and the DIA might lead one to suppose the existence of a functional as well as a morphological correspondence.
本实验的目的是验证泄殖腔膜的起源是外胚层还是内胚层。制备了一种针对泄殖腔最后部分上皮细胞的兔血清。将间接免疫荧光法应用于用低温恒温器获得的切片，这些切片被小心切割，以便包括泄殖腔的一部分、法氏囊 - 泄殖腔柄、泄殖腔膜和法氏囊皱襞。通过这种方式，可以证明泄殖腔、法氏囊 - 泄殖腔柄和泄殖腔膜的上皮呈现出强烈的荧光，而在法氏囊皱襞的上皮水平未观察到这种荧光。这些发现似乎表明，泄殖腔膜与泄殖腔和法氏囊 - 泄殖腔柄一样，起源于外胚层。此外，组织学研究表明，泄殖腔膜与泄殖腔的背壁呈现出密切的结构相似性。在这两个区域，都可以看到固有层中无组织的淋巴浸润，并且上皮没有显示出任何与滤泡相关的上皮细胞。腺体常常呈现出含有肠道转运物质的扩张隐窝的样子。这些腺体的上皮在不同点显示出淋巴浸润，并且在其管腔中检测到细胞聚集并不罕见。在这两个区域的固有层中也可以观察到几组嗜酸性粒细胞，在泄殖腔膜水平明显占优势。泄殖腔和泄殖腔膜之间的这些相似性可能会使人推测存在功能以及形态上的对应关系。
