Wrobel K H, Dostal S, Schimmel M
Institut für Anatomie, Universität Regensburg, Federal Republic of Germany.
Cell Tissue Res. 1988 Jun;252(3):639-53. doi: 10.1007/BF00216652.
The postnatal development of intertubular cells and vessels and of the tubular lamina propria was studied in three locations of perfusion-fixed bovine testes from 31 animals ranging from 4 to 78 weeks. The postnatal morphological differentiation of the testis is not uniform, regional differences have to be considered. The intertubular cell population is composed of mesenchyme-like cells, fibrocytes, Leydig cells, peritubular cells and mononuclear cells. In 4- and 8-week-old testes mesenchyme-like cells are the dominating element. These pluripotent cells proliferate by frequent mitoses and are the precursors of Leydig cells, contractile peritubular cells and fibrocytes. Morphologically differentiated Leydig cells are encountered throughout the entire period of postnatal development. In 4-week-old testes degenerating fetal and newly formed postnatal Leydig cells are seen in juxtaposition to each other. From the 8th week on, only postnatal Leydig cells are present. Between 16 and 30 weeks large-scale degeneration of prepuberal Leydig cells is observed. The Leydig cells that survive this degenerative phase constitute the long-lasting adult population. 20-30% (numerically) of all intertubular cells at all ages are free mononuclear cells. These are found as lymphocytes, plasma cells, monocytes, macrophages and light intercalated cells (LIC). The latter are monocyte-derived, Leydig cell-associated typical cells of the bovine testis. The differentiation of the two main components of the tubular lamina propria, (i) basal lamina and (ii) peritubular cell sheath, seems to be effected rather independent from each other and also from hormonal signals important for the development of the germinal cells. The laminated basal lamina reaches nearly 3 micron at 16 weeks and is later on continuously reduced. At 25 weeks the peritubular cells have transformed into contractile myofibroblasts. At this period the germinal epithelium is still in a prepuberal state.
研究了31头4至78周龄牛睾丸灌注固定后三个部位的管周细胞、血管及管周固有层的产后发育情况。睾丸的产后形态分化并不均匀，必须考虑区域差异。管周细胞群由间充质样细胞、纤维细胞、睾丸间质细胞、管周细胞和单核细胞组成。在4周和8周龄的睾丸中，间充质样细胞是主要成分。这些多能细胞通过频繁的有丝分裂增殖，是睾丸间质细胞、收缩性管周细胞和纤维细胞的前体。在整个产后发育期间都能见到形态分化的睾丸间质细胞。在4周龄的睾丸中，可见退化的胎儿型和新形成的产后睾丸间质细胞并列存在。从第8周开始，仅存在产后睾丸间质细胞。在16至30周期间，观察到青春期前睾丸间质细胞大量退化。在这个退化阶段存活下来的睾丸间质细胞构成了持久的成年细胞群。在所有年龄段，所有管周细胞中有20 - 30%（数量上）是游离单核细胞。这些细胞包括淋巴细胞、浆细胞、单核细胞、巨噬细胞和浅色插入细胞（LIC）。后者是单核细胞衍生的、与睾丸间质细胞相关的牛睾丸典型细胞。管周固有层的两个主要成分，即（i）基膜和（ii）管周细胞鞘，其分化似乎相当独立于彼此，也独立于对生殖细胞发育重要的激素信号。分层的基膜在16周时达到近3微米，随后持续减少。在25周时，管周细胞已转化为收缩性肌成纤维细胞。此时，生殖上皮仍处于青春期前状态。
