Clonal development of interconnected germ cells in the rat and its relationship to the segmental and subsegmental organization of spermatogenesis.
Clonal development of interconnected germ cells in the rat and its relationship to the segmental and subsegmental organization of spermatogenesis.
复制标题
大鼠中相互连接的生殖细胞的克隆发育及其与精子发生的节段和亚节段组织的关系。
DOI：
10.1002/aja.1001920203
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Russell,LD
中科院分区：
文献类型：
--
作者：
Ren,HP;Russell,LD
节和亚节是迄今为止在曲细精管纵切面中描述的最小的同步单位。众所周知，通过细胞间桥连接的克隆细胞处于相同的发育阶段，也被认为是同步的单位。这项研究旨在确定是否有可能在细胞间桥连接的细胞中看到的同步性与沿曲细精管长轴沿着编目的同步性相同。在本研究中，获得了最大数量的大鼠精子细胞连接的细胞间桥（克隆）。有人假设，如果克隆的大小大于已知的最小单位的同步（节或亚节）在曲细精管的长轴，然后细胞间的桥梁将最有可能支配同步发展的节或亚节（或更精细的细分）。如果克隆的大小小于存在于一个片段或亚片段中的细胞数量，那么其他因素必须控制小管纵向方面的同步性。在精子细胞克隆大小的测定中，向大鼠睾丸注射细胞松弛素D，它打开精子细胞克隆的细胞间桥以产生大的共质体。共质体中的细胞核数量是从连续切片的组织中确定的，通过用照相机绘制细胞核，并通过计数细胞核。在对小管进行广泛检查后，在观察到的疑似5个最大克隆中发现的精子细胞数量确定为650、607、338、240和177。根据先前发表的数据确定每给定小管长度的精子细胞的节段和亚节段长度和密度。最小节和亚节内精子细胞数分别为128个和30个。我们的观察结果表明，生殖细胞沿着小管长度的同步发育是由细胞间桥控制的，因为填充一个节段或亚节段所需的联合细胞的数量大于迄今为止编目的最小的任意鉴定的同步单位中的细胞数量。
Segments and subsegments are the smallest unit of synchrony thus far described within longitudinal sections of seminiferous tubules. It is known that cells in a clone joined by intercellular bridges are at the same phase of development and are also thought to be units of synchrony. This study was designed to determine if it is possible that the synchrony seen in cells joined by intercellular bridges is the same as that cataloged along the long axis of the seminiferous tubule. In the present study, the maximum number of rat spermatids joined by intercellular bridges (a clone) was obtained. It was hypothesized that if the clone size were larger than the smallest known units of synchrony (segments or subsegments) in the long axis of the seminiferous tubule, then intercellular bridges would most likely govern the synchronous development of segments or subsegments (or finer subdivisions thereof). If the clone size is smaller than the number of cells present in a segment or subsegment, then other factors must govern synchrony in the longitudinal aspect of the tubule. In the determination of spermatid clone size, rat testes were injected with cytochalasin D which opens intercellular bridges of a spermatid clone to produce large symplasts. The number of nuclei in the symplasts was determined from serially sectioned tissue, by drawing nuclei with a camera‐lucida, and by counting nuclei. After extensive examination of tubules, the number of spermatids found in the suspected five largest clones observed was determined to be 650, 607, 338, 240, and 177. The segment and subsegment length and the density of spermatids per given tubule length were determined from previously published data. The numbers of spermatids accommodated in the smallest segment and subsegment were 128 and 30, respectively. Our observations indicate that synchronous development of germ cells along the length of the tubule is controlled by intercellular bridges since the number of conjoined cells required to fill a segment or subsegment is more than the number of cells in the smallest arbitrarily identified units of synchrony cataloged to date.