Arenas M I, Bethencourt F R, Fraile B, Paniagua R
Department of Cell Biology and Genetics, University of Alcalá, Alcalá de Henares (Madrid), Spain.
Histochem Cell Biol. 1997 Jun;107(6):469-77. doi: 10.1007/s004180050134.
A light and electron microscope immunohistochemical study of the tunica albuginea from both young and elderly men was carried out to determine the distribution of the cells that contain actin, vimentin and/or desmin, and to evaluate the possible variations with ageing by means of quantitative studies. Testicular volume and testicular parenchyma volume decreased significantly with age whereas the tunica albuginea volume remained unchanged. These results agree with the scanty quantitative changes observed in the testicular connective tissue with age, and the notion that age-related changes in testicular volume are principally restricted to the seminiferous tubules. Three connective tissue layers could be distinguished in the tunica albuginea in both young and elderly men. The middle and inner layers increased in width with age while the width of the outer layer decreased. The average width of the tunica albuginea increased significantly with ageing. The tunica albuginea of young men and elderly men presented two types of fusiform cells: (1) fibroblast-like cells, which immunoreacted to actin and vimentin, but not to desmin; and (2) myoid cells, which immunoreacted to actin, vimentin and desmin. In both young men and elderly men, the total number of desmin-positive cells (myoid cells) was significantly lower than that of fibroblasts. However, the total number of desmin-positive cells was significantly increased in ageing men. In young testes, desmin-positive cells were more abundant in the outer layer of the tunica albuginea, whereas in elderly men these cells predominated in the middle layer. The increased desmin immunoexpression in the tunica albuginea of ageing men contrasts with the decrease in desmin immunoreaction in other myoid cells of the testis, the peritubular myoid cells, but only in seminiferous tubules that showed severe germ cell depletion. This suggests that changes in intermediate filament immunoexpression in peritubular cells are focalised, and thus, under local control, whereas changes in the tunica albuginea cells are generalised and possibly related to factors also affecting the connective tissue in other organs.
对年轻男性和老年男性的白膜进行了光镜和电镜免疫组织化学研究，以确定含有肌动蛋白、波形蛋白和/或结蛋白的细胞分布，并通过定量研究评估随年龄增长可能出现的变化。睾丸体积和睾丸实质体积随年龄显著减小，而白膜体积保持不变。这些结果与睾丸结缔组织随年龄观察到的少量定量变化一致，以及睾丸体积的年龄相关变化主要局限于生精小管的观点相符。在年轻男性和老年男性的白膜中均可区分出三层结缔组织。中层和内层宽度随年龄增加，而外层宽度减小。白膜的平均宽度随年龄增长显著增加。年轻男性和老年男性的白膜呈现两种梭形细胞：（1）成纤维细胞样细胞，对肌动蛋白和波形蛋白免疫反应阳性，但对结蛋白免疫反应阴性；（2）类肌细胞，对肌动蛋白、波形蛋白和结蛋白免疫反应阳性。在年轻男性和老年男性中，结蛋白阳性细胞（类肌细胞）的总数均显著低于成纤维细胞。然而，老年男性中结蛋白阳性细胞的总数显著增加。在年轻睾丸中，结蛋白阳性细胞在白膜外层更为丰富，而在老年男性中，这些细胞在中层占主导。老年男性白膜中结蛋白免疫表达的增加与睾丸其他类肌细胞（睾丸周类肌细胞）中结蛋白免疫反应的减少形成对比，但仅在显示严重生殖细胞耗竭的生精小管中如此。这表明睾丸周细胞中间丝免疫表达的变化是局部化的，因此受局部控制，而白膜细胞的变化是全身性的，可能与也影响其他器官结缔组织的因素有关。
